Advanced Melt Filtration for Highly Contaminated Recycled Polymers: Strategies and Technologies for Production EfficiencyDiscover Melt Filtration Solutions for Complex Recycled Materials: Continuous Backwash, Scraper, and Laser SystemsBy Marco ArezioThe polymer recycling sector is constantly growing, driven by increasing demand for sustainability and the need to reduce environmental impact. However, managing highly contaminated plastic waste streams presents one of the most significant challenges. Impurities like metals, paper, wood, textile fibers, and particularly gels (degraded or cross-linked polymers) can severely compromise final product quality and extrusion process efficiency.Melt filtration is a critical operation aimed at removing these impurities, ensuring high-quality recycled polymer and minimizing production interruptions. Traditional filtration systems often can't meet the demands of highly contaminated materials, leading to frequent machine shutdowns for cleaning or replacing filter elements. This technical article explores the latest innovations in the design and optimization of melt filtration systems, capable of handling high levels of impurities and gels, significantly improving production efficiency and the sustainability of the recycling process.The Evolution of Melt Filtration Systems: Beyond the Screen ChangerWhile effective for materials with low contaminant percentages, screen changers show their limitations with post-consumer recyclates. Their limited filter surface area and the need for frequent interruptions for cleaning or replacement make them unsuitable for high-contamination applications. Research and development have led to the introduction of more sophisticated technologies designed for continuous operation or with minimal downtime, ensuring higher productivity and better product quality.Continuous Backwash Filters: The Solution for Uninterrupted OperationContinuous backwash filters represent a milestone in the evolution of melt filtration. Their operating principle is based on the presence of two or more filter elements (screens or cartridges) operating in parallel. When a filter element becomes clogged, a portion of the clean melt is diverted and flowed in reverse through the clogged element, expelling the accumulated impurities. This process happens automatically and without interrupting the main flow, allowing for continuous production.More advanced systems use differential pressure sensors to monitor the degree of clogging and initiate backwashing only when necessary, optimizing efficiency and reducing material waste. The effectiveness of these systems depends on the correct design of the screen geometry and the management of pressure and temperature during backwashing.Scraper Filters: Robustness and Self-Cleaning for Abrasive ContaminantsScraper filters, also known as self-cleaning screen changers, are particularly well-suited for handling materials with high amounts of fibrous, abrasive, or large impurities. These systems feature a cylindrical or conical filter element, on whose inner or outer surface a blade or scraping system rotates.Impurities are mechanically removed from the filter surface and conveyed to a collection chamber, from which they can be periodically discharged without interrupting the process. The robustness of these filters makes them ideal for heavy-duty applications where other systems might suffer damage or rapid clogging. Optimizing blade design and rotation speed is crucial for maximizing cleaning efficiency and minimizing wear.Laser Technologies for Filtration: Unprecedented Precision and DurabilityOne of the most promising innovations in melt filtration is the application of laser technology. Laser filters use a matrix of microscopic holes precisely created by laser on a rotating drum or plate. The melt passes through these holes, while larger impurities are retained on the surface. A scraping system or an air/gas jet continuously removes impurities from the drum surface.The size and shape of the holes can be controlled with extreme precision, allowing for very fine filtration and greater efficiency in removing gels. The durability of laser filter elements is superior to traditional screens, reducing maintenance costs and downtime. This technology is particularly advantageous for producing thin films or fibers, where even minimal impurities can severely compromise product quality.Managing Gels and Micro-Impurities: Challenges and Integrated SolutionsGels pose a unique challenge in melt filtration. Being polymeric in nature, they often have a similar density to the molten polymer and can deform under pressure, making mechanical removal difficult. Innovations in filter element design, such as the use of spiral or "labyrinth" geometries, and the optimization of operating conditions (temperature and pressure) can improve the efficiency of gel capture. Furthermore, integrating multiple filtration stages with different finenesses and filter types (e.g., a scraper filter for larger impurities followed by a backwash or laser filter for micro-impurities and gels) is an effective strategy to address the complexity of highly contaminated recyclates.Process Optimization: Monitoring, Automation, and Predictive MaintenanceThe efficiency of a filtration system depends not only on the filter technology but also on its integration into the extrusion process. Advanced monitoring systems, which continuously measure differential pressure, temperature, and flow rate, allow for real-time detection of filter element clogging and automatic activation of cleaning or backwashing procedures. The automation of impurity discharge systems and intelligent management of cleaning cycles minimize human intervention and maximize uptime.Implementing predictive maintenance strategies, based on the analysis of operational data, allows for anticipating the wear of filter elements and planning maintenance interventions, avoiding unscheduled machine shutdowns.Impact on Final Product Quality and Economic SustainabilityThe adoption of advanced filtration systems directly impacts the quality of recycled polymer. Efficient removal of impurities and gels results in a product with improved mechanical, optical, and aesthetic properties, making it competitive with virgin polymers for a wide range of applications. This not only increases the value of the recycled material but also opens new market opportunities.From an economic perspective, reduced machine downtime, optimized energy consumption (due to lower filtration pressure), and decreased waste contribute to a significant reduction in operating costs and an increase in the overall profitability of the recycling process.Future Prospects: Artificial Intelligence and Self-Cleaning MaterialsThe future of melt filtration for highly contaminated recyclates is moving towards even more intelligent and autonomous solutions. The integration of Artificial Intelligence (AI) and Machine Learning (ML) will allow filtration systems to "learn" from the behavior of the melt and impurities, dynamically optimizing operational parameters to maximize the efficiency and lifespan of filter elements.Research into self-cleaning materials and surfaces with anti-adhesive properties could further revolutionize filter design, reducing the frequency of cleaning operations and extending component lifespan. These innovations will open new frontiers for polymer recycling, making it even more efficient, sustainable, and economically advantageous.© All rights reserved
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What are Self-extinguishing Polymers (Flam Retard): Applications and DifferencesAdditives, Laboratory Tests, Differences, and Commercial and Industrial Applications of Flame Retardant PolymersFlame retardant plastics are polymeric materials modified to resist ignition and slow the spread of flames. This property is particularly important in numerous applications, such as electronics, construction, and transportation, where fire resistance is crucial for safety. The addition of flame retardant additives is the most common method to confer fire-resistant properties to plastics. Types of Flame Retardant Additives Flame retardant additives are classified into different categories, depending on their chemical composition and action mechanism: Halogenated Additives: Include compounds based on bromine and chlorine. They work by releasing halogens that interfere with the combustion reaction in the gas phase. Phosphorus Additives: Operate mainly in the solid phase, promoting carbonization and reducing the amount of flammable material vaporized. Metal Hydroxides: Such as aluminum and magnesium hydroxide, these additives release water when heated, which helps cool the material and dilute combustible gases. Intumescent Additives: Form a protective carbonaceous foam on the material's surface when exposed to heat, insulating the underlying material from the heat source. Flame Inhibition Mechanism Flame inhibition in plastics works through various mechanisms, depending on the type of additive used: Dilution of Combustible Gases: Some additives release inert gases that dilute the combustible gases in the flame area, reducing combustion. Physical Barrier: Intumescent additives form a carbonaceous barrier that thermally isolates the material and prevents oxygen access. Cooling: The water released by metal hydroxides absorbs heat, lowering the combustion temperature. Chemical Interference: Halogens and other compounds can interfere with the radical reactions in the combustion zone, slowing down the reaction. Laboratory Tests to Catalog Non-Flammable Plastics Let's see what are the main tests to catalog the flammability grade and how they are performed: UL 94 Test The UL 94 test, managed by Underwriters Laboratories (UL), is one of the most recognized and widely used methods to assess the flammability properties of polymeric materials used in electrical and electronic devices. This test classifies materials based on their ability to extinguish flames after being ignited under controlled conditions. The test is performed by applying a flame to a material sample for a specific period and observing the material's behavior in terms of combustion time after flame removal, dripping of flammable material, and length of combustion. Based on the results, materials are classified into different categories, such as V-0, V-1, V-2, HB, 5VB, and 5VA: V-0, V-1, V-2: Indicate that the material self-extinguishes within a certain time after ignition. The distinction between classes depends on the self-extinguishing time and the presence of dripping of inflamed particles. HB: The lowest classification, indicates a horizontal burning speed within a certain range. 5VB and 5VA: Are more severe tests that assess the resistance to ignition when the sample is subjected to a high thermal load. 5VA represents the maximum flame resistance without material dripping, while 5VB: Allows some dripping.Limiting Oxygen Index (LOI) Test The Limiting Oxygen Index (LOI) test measures the minimum percentage of oxygen in the atmosphere necessary to support the combustion of a polymeric material. It is performed in a special apparatus where the sample is placed in a glass column and exposed to a controlled mixture of nitrogen and oxygen, gradually increasing the oxygen concentration until the material continues to burn for a predetermined time after ignition. The LOI value is a direct measure of the material's flammability: the higher the LOI value, the less flammable the material. Materials with LOI values above 21% (the percentage of oxygen in the air) are considered more resistant to fire. This test is particularly useful for comparing the fire resistance of different materials under a single standardized metric. Cone Calorimeter Flammability Test The cone calorimeter flammability test is an advanced method that provides detailed data on a material's response to heat exposure. During the test, a material sample is exposed to an increasing radiant flux in the presence of an ignition source, simulating the effects of an early-stage fire. The cone calorimeter measures the heat release rate, smoke production, and mass loss of the sample over time, providing a complete profile of its reactivity to fire. These data help understand how the material will contribute to the growth and spread of fire, allowing engineers to design materials and products with improved fire safety performance. This test is particularly useful in evaluating materials for construction and transportation engineering. Making a Recycled Polymer Flame Retardant The process of making a recycled polymer flame retardant, both post-consumer and post-industrial, requires careful selection of additives compatible with the type of polymer and maintaining the mechanical properties of the recycled material. The process includes: Material Analysis: Identification of the recycled polymer's composition to choose the most suitable additives. Additive Incorporation: Additives can be mechanically mixed with the polymer during the extrusion process or can be applied as surface coatings. Maintaining Characteristics after Mechanical Recycling Mechanical recycling can affect the flame retardant properties of polymers due to the thermal or mechanical degradation of the polymer and additives during the recycling process. - The stability of flame retardant properties in a recycled polymer depends on: - The thermal stability of the flame retardant additives. - The compatibility of the additives with the recycling process. - The ability to uniformly redistribute the additives in the polymer during recycling. To maintain the flame retardant characteristics, it may be necessary to add further additives or stabilizers during the recycling process. Evaluating the properties of the recycled material through laboratory tests is crucial to ensure that the recycled material meets safety and performance requirements. Use of Self-Extinguishing Polymers for the Production of Industrial and Civil Use Articles Flame retardant polymers are used in a wide range of applications, especially in construction, where fire resistance is crucial for building safety. These materials are designed to reduce the speed of combustion, limit the spread of flames, and help prevent fires. In construction, flame retardant polymers find application in numerous products, including thermal insulators, coatings, electrical cables, and structural components. Flame Retardant Polymers Used in Construction Expanded Polystyrene (EPS) and Extruded Polystyrene (XPS): Widely used as thermal insulators for exterior coats and for insulating floors, roofs, and walls. They can be treated with flame retardant additives to reduce flammability. Expanded Polyethylene (EPE): Used for thermal insulation and impact cushioning, EPE can be modified to improve fire resistance, making it suitable for construction applications. Intumescent Polymers: These materials expand when exposed to heat, forming a carbonaceous barrier that protects the underlying material from flames. They are used in paints, mastics, and coatings for electrical cables. Flame Retardant Polyvinyl Chloride (PVC): PVC is used in a variety of construction applications, including cable sheathing and pipes. PVC can be made flame retardant through the addition of specific additives. Phenolic Polymers: These materials are known for their excellent fire resistance properties and are used in insulating foams and composites. Applications of Self-Extinguishing Articles in Construction Thermal Insulation: Flame retardant insulating materials are essential to prevent the spread of fire through wall cavities and other insulated spaces in buildings. Coatings and Paints: Provide passive fire protection to structures, beams, and columns, helping to maintain structural integrity in case of fire. Electrical Cables and Pipes: The use of flame retardant materials in these components reduces the risk of electrical fires and limits the spread of fire. Differences in Fire Resistance of Insulators for Thermal Coats Thermal insulators can vary significantly in their fire resistance depending on the material, density, and presence of flame retardant additives. Here are some key differences: Thermal Resistance: Some insulators, such as those based on mineral fiber (rock wool, glass wool), offer better fire resistance performance compared to organic ones (EPS, XPS) due to their incombustible nature. Emission of Smoke and Toxic Gases: Organic materials tend to produce dense smoke and toxic gases when burned, while inorganic materials perform better in this aspect. Fire Reaction Classification: Insulating materials are classified according to European standards (for example, Euroclasses A1, A2, B, C, etc.) that indicate their reactivity to fire. Materials classified as A1 are non-combustible, while those in class B, C, etc., have increasing levels of flammability. Application and Thickness: The fire resistance of an insulator can also depend on the specific application and the thickness of the material. The greater the thickness, the better the fire resistance can be, but this also depends on the material's composition and the presence of flame retardant additives. For example, a thicker insulator can offer a longer fire resistance time because it takes longer to be completely compromised by flames. However, it's not just thickness that determines effectiveness; the quality of the material and its ability to resist fire propagation are equally crucial. In insulating materials, flame retardant additives can act in synergy with thickness to improve fire resistance. Materials with greater density or treated with specific chemical additives can exhibit superior performance even at thinner thicknesses. Therefore, selecting the appropriate insulating material for a specific application requires careful consideration not only of physical properties like thickness but also of chemical composition and fire resistance capability. In the construction sector, current regulations often specify minimum requirements for the fire resistance of insulators, taking into account both thickness and material composition. These standards ensure that materials used in buildings provide an adequate level of protection in case of fire, thus contributing to the safety of occupants and the preservation of the structure itself.
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Surface Quality Optimization in High Speed Machining of PlasticsAdvanced Strategies for Enhancing Precision, Stability, and Finish in HSM Processingby Marco ArezioHigh-Speed Machining (HSM) represents a cutting-edge technology for processing plastic materials. Widely utilized in the automotive, aerospace, and medical sectors, this technique enables high levels of precision and efficiency. However, the success of the process relies on the ability to optimize surface quality, a critical aspect for both the aesthetics and functional performance of the final product. Let us delve into the key factors influencing this crucial parameter.Characteristics of Plastic MaterialsPlastics offer extraordinary versatility, but their processing poses specific challenges related to their chemical and physical properties. For example, thermoplastics such as polyethylene (PE) and polycarbonate (PC) tend to melt under heat, facilitating certain operations but requiring stringent temperature control. In contrast, thermosetting materials like epoxy resins withstand high temperatures better but are less malleable during cutting.The hardness and brittleness of the material directly affect its behavior during machining. A material that is too brittle may fracture, while one that is too hard can create high cutting resistance. Furthermore, the low thermal conductivity typical of plastics increases the risk of deformation and surface burns, emphasizing the importance of advanced thermal control.Processing ParametersAchieving a high-quality surface finish requires precise regulation of processing parameters. Cutting speed, for instance, must be high enough to minimize burrs but not so high as to cause overheating. Similarly, feed rate and cutting depth must be balanced to avoid vibrations and ensure uniformity.A cutting speed that is too low compromises productivity, while excessive cutting depth can lead to instability. Selecting optimal values for each parameter depends on the type of plastic and the specific application requirements.Importance of the ToolTools play a central role in high-speed machining of plastics. The geometry and material of the tool must be carefully designed to reduce material build-up and prevent overheating. Tools made of polycrystalline diamond (PCD) or titanium nitride (TiN)-coated materials offer excellent performance due to their wear resistance and extended durability.Regular maintenance of tools is equally important: sharp tools minimize surface defects such as burrs or streaks, ensuring a uniform finish. Additionally, using automated monitoring systems to detect signs of wear can significantly improve overall process efficiency and quality.Thermal PhenomenaThe heat generated during high-speed machining is one of the primary challenges to achieving good surface quality. High temperatures in the cutting zone can cause melting, deformation, or alterations to the mechanical properties of the material.To manage these phenomena, advanced cooling systems such as compressed air flows or liquid coolants are used to dissipate excess heat. In parallel, high-performance lubricants reduce friction and help maintain stable operating conditions. The choice of the most suitable technology depends on the specific material characteristics and machining process.Vibrations and StabilityVibrations are a major cause of surface defects in high-speed machining. They can result from insufficient machine rigidity, worn tools, or improperly optimized cutting parameters. A rigid and stable machine structure is essential to minimize unwanted oscillations.Controlling the system's natural frequencies helps prevent resonance phenomena, which amplify vibrations and compromise the finish. Advanced sensors and real-time monitoring systems are useful tools for promptly identifying and addressing potential problems.Working EnvironmentA controlled working environment significantly contributes to machining quality. Cleanliness reduces the risk of contamination that can alter the interaction between the tool and the material, while maintaining stable temperature and humidity levels prevents undesired variations in the workpiece properties.Examples of Applications in Plastic MachiningHigh-Speed Milling of Polycarbonate (PC)Industry: Transparent components for lighting and optical lenses.Approach: Using titanium nitride (TiN)-coated cutters to achieve smooth, streak-free surfaces, enhancing optical efficiency.Compression Molding with HSM FinishingIndustry: Interior panels for automobiles.Approach: High-speed finishing with diamond tools to reduce aesthetic defects and ensure uniform surfaces.Micromachining of Thermoplastics for Medical DevicesIndustry: Production of PEEK components for medical implants.Approach: Cooling systems with compressed air flows and carbide tools to minimize thermal deformation.Laser Cutting of Plastics with Subsequent HSM ProcessingIndustry: Acrylic components for electronic devices.Approach: Refining laser cutting residual irregularities with low-depth milling cutters.Machining of Polymer Foams (EPS or PU)Industry: Prototypes or models.Approach: Using tools with specific geometries to avoid residue and achieve precise machining.Finishing of 3D Printed ComponentsIndustry: Components in PLA or ABS for prototypes.Approach: HSM milling with lubrication to improve surface finish.High-Speed Polishing of Transparent Plastic MaterialsIndustry: Acrylic screens for displays.Approach: Diamond cutters ensure perfectly smooth surfaces.ConclusionsThe quality of the surface in high-speed machining of plastics depends on a balance of multiple factors: material properties, processing parameters, tool selection and maintenance, thermal management, and vibration control. Deepening knowledge of these aspects allows companies to improve product quality, reduce waste, and increase competitiveness. Investing in advanced technologies and training is essential to meet the challenges of an ever-evolving market.© Reproduction Prohibited
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Microbiological research to study a bacterium that decomposes the polyurethanePseudomonas is a bacterium, which could break down the bonds of thermosetting resin such as polyurethane Among the various study activities, on alternative routes in waste management, microbiology is striving to find and test bacteria to break down those chemical bonds defined as irreversible, such as those of polyurethane. The thermosetting resins, of which polyurethane is part, is a very rigid material made up of cross-linked polymers in which the motion of the polymer chains is severely limited by the high number of existing cross-links. During heating they undergo an irreversible chemical modification. Resins of this type, under the action of heat in the initial phase, soften (become plastic) and subsequently solidify. Unlike thermoplastic resins, they do not have the possibility of undergoing numerous forming processes during their use. Thermosetting resins are materials in which the motion of the polymer chains is strongly constrained by a large number of existing crosslinking. In fact, during the production process, they undergo irreversible chemical changes associated with the creation of transverse covalent bonds between the chains of the starting pre-polymers. The density of the interconnections and the nature depend on the polymerization conditions and the nature of the precursors: generally, they are liquid systems, or easily liquefiable when hot, made up of low molecular weight organic compounds, often multifunctional, chemically reactive, sometimes in the presence of initiators or catalysts. Polyurethane is a compound widely used as a thermal insulator, in the construction sector, the car industry, in household appliances, in cold storage, in the naval and railway sector, in furniture, in the footwear sector and in many other industrial sectors. Every year, in Europe alone, about 3.5 million tons of polyurethane are produced which, at the end of the life cycle, does not find a correct destination in the recycling sector and normally end up in landfills. The difficulty that this typology of plastic waste encounters in the reconversion process today, until the chemical recycling has taken hold, have pushed biological research to trace new paths. A European research group called P4SB is studying materials from synthetic biology that are able, through bacterial catalysts, to create bio enzymes that can depolymerize polyurethane, but also PET. The study identified a bacterium, called Psneudomonas, which, properly engineered, is able to metabolize the components of the polyurethane, which will then be made, within the bacterial mass, in the form of bioplastic. This bacterium has the ability to survive in extreme conditions and is very resistant to toxic substances, in fact it is an enemy par excellence in the medical field as it easily resists antibiotics. It is part of the family of gram-negative bacteria that normally affects people with low immune barriers or problems with the skin and mucous membranes. The bacterium in humans triggers diseases associated with infections, such as respiratory problems, pneumonia, endocarditis, meningitis, eye, joint, gastrointestinal, dermatological and other forms of body reaction. This shows that it is a bacterium to be taken seriously and its use in the microbiological field, applied to the recycling of plastics such as polyurethane, makes it clear the degree of colonization and decomposition that it could put in the field if treated with due care.
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Assembly of Plastic Components after ProductionWhich systems to use for the assembly of the plastic components produced There are plastic products that are printed or extruded individually and assembled together in successive phases, with the aim of creating a finished product composed of several parts. The activity of assembling the various pieces, and their tightening, involves an in-depth analysis of which closing tools to use, to be compatible with plastic materials used and also functional with the use of the finished product. The main fixing systems of the plastic components can be grouped into: • Fixing with plastic screws • Fixing with metal screws • Fastening through nailing • Fixing by welding • Fixing through compression Plastic Screws The fixing of the elements to be assembled through the use of plastic screws has a limited use, as they express low mechanical strength and low rigidity. Despite their low structural performance, plastic screws find great use in those products where continuous electrical insulation, very high resistance to corrosion and a continuity of the shades of the chosen color, to make the product chromatically more continuous. Metal Screws Fastening with metal screws is by far the most used method to assemble plastic elements, due to the excellent mechanical resistance and good grip between plastic and metal element. The screws can be metric or self-tapping. Those metrics, in some mechanical situations, may present some sagging of the flanks that are threaded into the plastic material, this can be caused in the presence of a low elastic modulus of the polymer that makes up the plastic element. In fact, the mechanical resistance of a metric thread in plastic is generally limited, so it is advisable to use metric screws with internal threaded brass inserts. These inserts are inserted, before molding in the mold itself or later through the use of ultrasound. From an economic point of view it is almost never convenient to use this type of inserts, due to the waste of time in their positioning, however the use of a screw metrica makes subsequent product assembly faster. The self-tapping ones are made up of different shapes and threads based on the mechanical work they have to perform and the type of plastic they will be inserted into. The threads can be more or less close together, therefore with a number of different spirals, have inclination angles of the spirals from 30 to 60° and a diameter of soul of the vine and its variable spiral. In the case, for example, of products made with thermosetting resins, it is absolutely necessary to use self-tapping screws, in fact this type of polymer does not conform, like other plastics , to the screw, but is drilled with the removal of the resulting chip. In this case, an asymmetrical screw profile with a 30 ° spiral angle is recommended. Nailing Another type of assembly of plastic components can take place with the method of nailing the elements. The moldable nails used are generally composed of brass, copper, aluminum or with hollow nails to be turned. If we use nails to be turned, the impulse of the beating must always take into account the resistance to breaking and cracking of the plastic polymer we are working on, having the foresight to calculate the ratio between mass and typing speed well. If the elements to be assembled are made of thermoplastic material, the end of the core of the product can be finished hot or cold on the nail head. Welding Thermoplastic materials can also be assembled through the welding process with friction methods, with ultrasound or with hot tools. It must always be taken into consideration that the welding point or the welded ends, if continuous, will never have a mechanical strength comparable to the base element. Furthermore, the welding phases can create internal tensions with respect to the molecules of which the polymer is made and, when present, interact negatively on the reinforcing fibers. Generally speaking, based on the plastics and the type of weld, experience in the field tells us that the mechanical strength of a weld can be lower between 40 to 80% of the original plastic material. This weakening is also accentuated if the product has to withstand high loads over time or withstand particular dynamic stresses or chemical attacks on the plastic material. Assembly by compression The assembly system by compression of the elements is the cheapest and fastest, however some important considerations must be made. If there are situations of interlocking assembly between plastic and metal elements, it is a good rule to plan the calculation of the compressive stresses calibrated on plastic materials and not on metal ones. Furthermore, when the elements will be in operation, for example the parts of a fan, it is necessary to keep in mind the greater thermal expansion of the plastic compared to the metal elements and, in the case of hygroscopic polymers, also the possible swelling. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Cellulose ethers: production, industrial applications and prospects in the recycling of natural polymersFrom Synthesis to Sustainability: The Role of Cellulose Ethers in Construction, Paints and Advanced Polymeric Materials by Marco Arezio The search for high-performance polymeric materials with a low environmental impact has led, in recent decades, to a growing interest in cellulose derivatives. Cellulose is the most abundant natural polymer on Earth, a renewable resource extracted from wood, cotton and other fibrous plants. Through targeted chemical processes, cellulose is transformed into a wide range of cellulose ethers, including methylcellulose (MC), hydroxyethylcellulose (HEC), hydroxyethylmethylcellulose (HEMC) and hydroxypropylmethylcellulose (HPMC). These materials, thanks to their unique properties, have revolutionized the construction, paint and even advanced polymer industries. What are cellulose ethers? Cellulose ethers are derivatives obtained through an etherification reaction of raw cellulose. In practice, some hydroxyl groups (-OH) of the glucosidic units of cellulose are replaced by alkyl or hydroxyalkyl groups, which modify the solubility and rheological properties of the starting polymer. This process allows to obtain materials that, while maintaining the basic structure of cellulose, acquire new functionalities: they become more easily soluble in water, more stable and more versatile in industrial processes. Cellulose ethers are not only technically advanced materials, but also represent an ecological solution. In fact, their production starts from renewable resources and, compared to many synthetic polymers of fossil origin, has a potentially lower environmental impact. How cellulose ethers are produced The production of cellulose ethers involves several steps, all carried out under controlled industrial conditions: - Cellulose preparation: cellulose is first purified, eliminating lignin and hemicelluloses through bleaching and hydrolysis processes. The starting material can be wood pulp, cotton or plant residues of various origins. - Activation: Cellulose is treated with an alkaline solution (usually sodium hydroxide), which makes the hydroxyl groups more reactive. - Etherification: in this phase the etherifying reagent is introduced (for example methyl chloride for methylcellulose, ethylene oxide for hydroxyethylcellulose, propylene oxide for hydroxypropylmethylcellulose). The degree of substitution, i.e. the quantity of ether groups introduced, is precisely controlled, since it directly influences the properties of the final product. - Neutralization and purification: the reaction mixture is neutralized, washed to remove by-products and finally dried. The resulting product is a white, odorless, fine-grained, highly pure powder. - Quality control: Product characteristics – moisture, ash content, bulk density, viscosity and pH – are rigorously monitored, as they influence performance in different applications. Uses of cellulose ethers in industry Cellulose ethers are now a mainstay in many industrial sectors, mainly due to their ability to modify the rheology and processability of numerous materials. Building In adhesives, cement mortars, fillers and cement-based products, the addition of cellulose ethers (especially hydroxyethyl methylcellulose, HEMC) improves workability, increases water retention and adhesive strength, and reduces slippage. This translates into easier and more efficient applications, as well as greater durability of the finished product. The ability to “hold” water in cementitious systems allows for better hydration and a more complete reaction of the binder, a key factor in the final quality of constructions. Paint industry In waterborne paints and decorative coatings, cellulose ethers are used as thickeners, stabilizers and suspending agents. In addition to ensuring uniform application, they prevent pigment settling and improve the appearance of the painted surface. Polymers and composite materials In recent years, research has focused on the use of cellulose ethers as rheological modifiers and compatibilizing agents in biodegradable polymers. Some studies have shown that, inserted into matrices such as polylactic acid (PLA) or other biopolymers, cellulose ethers improve filler dispersion, mechanical stability and material processability, paving the way for new applications in composite materials and sustainable packaging. Other sectors Cellulose ethers are also used in pharmaceuticals (as excipients and controlled release agents), in the food industry (as thickeners and stabilizers) and in the production of detergents, cosmetics and personal care products. Technical and performance advantages of cellulose ethers The large-scale adoption of cellulose ethers is motivated by a number of key advantages, supported by a vast scientific literature: - Excellent bond: improves the adhesion of mortars and fillers to the application surfaces. - Increased water retention: they delay evaporation, ensuring longer working times and a better chemical reaction in the mortars. - Slip resistance: makes it easier to apply materials on vertical surfaces without dripping. - Flexibility and ease of use: powders easily dispersible in water, compatible with many chemical systems. - Environmental compatibility: starting from a renewable natural base, they fit perfectly into circular economy models and green building projects. Cellulose ethers and recycling: between biodegradability and circularity One of the central themes in current research concerns the end-of-life of cellulose ethers and their compatibility with recycling processes. Although they are natural derivatives, the presence of ether groups modifies their biodegradability compared to pure cellulose. However, numerous studies have confirmed that many cellulose ethers, particularly those with low degrees of substitution, are nevertheless biodegradable under controlled environmental or industrial conditions (e.g. composting). In the industrial field, the possibility of reusing production waste or residues of cellulose ethers in new production cycles is becoming a reality, also thanks to the adoption of depolymerization processes or reuse in low environmental impact mixtures. In particular, the use of these materials in biodegradable polymer composites represents an interesting opportunity for “upcycling”, that is, the valorization of a residue in a higher quality product. Conclusions: Towards a sustainable supply chain of natural polymers Cellulose ethers embody a perfect balance between technology, sustainability and industrial performance. Their versatility, renewable origin and recycling prospects make them one of the most promising solutions for green construction, sustainable paints and innovation in advanced polymeric materials. In an era in which the demand for high-performance and at the same time ecological materials is increasingly pressing, cellulose ethers represent a concrete answer, supported by a solid scientific basis and by applications now consolidated in the manufacturing world. © Reproduction prohibited Main sources R. M. Rowell, “Handbook of Wood Chemistry and Wood Composites” (CRC Press, 2022). G. Heinze, “Cellulose Derivatives: Synthesis, Structure, and Properties,” in Polysaccharides, 2021. Y. Habibi et al., "Cellulose-Based Hydrogels: Synthesis, Properties and Applications," Carbohydrate Polymers, vol. 261, 2021. M. Vehviläinen et al., "Biodegradation of Cellulose Ethers in Industrial Composting," Waste Management, 2023. S. Gurgel et al., "Recent Advances on the Use of Cellulose Derivatives in the Building Industry," Construction and Building Materials, vol. 315, 2022. European Polysaccharide Network of Excellence (EPNOE), "Cellulose Ethers: Environmental Impact and Industrial Use," Technical Report, 2023.
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Pfas emergency in Plastics and Packaging Is there a solution?Pfas in plastics and packaging: they are chemical compounds not present in nature, not biodegradable and harmful to healthLike all the medals that are respected, also the Pfas, an acronym of the perfluoroalkyl and polifluoroalkyl substances, have their shiny side and their dark side. The chemical compounds of these families, which number about 4700, were created in the laboratory and widely used since the 1950s in the food packaging industry, in pesticides, in non-stick pans, in cardboard containers, in fire foams, in shampoos , in paints, in stain-resistant products and in many other applications. In plastics we find them in the form of elastomers (Vinylidene fluoride, Fluorurates in general, Tetrafluoroethylene) or in polymeric materials (Magnesium salt-sodium-fluoride of silicic acid). The advantages of these substances, applied to finished products, lies in their water repellency, oil-repellency and thermo-resistance , which allow us to make, for example, a waterproof jacket , not to stick an egg to the pan , not to get dirty mayonnaise or oily substances when we eat a sandwich filled with paper and not let our hands get dirty in the cinema when we eat popcorn. Their chemical bond composed of fluorine and carbon makes the resulting molecule an element irreplaceable today in industrial applications, but also makes it non-biodegradable and extremely dangerous, as it is odorless, tasteless and colorless. These characteristics allow it to be easily dispersed in water, soil and air, remaining to damage the environment and human health for a long time. The plants absorb the Pfas through the irrigation water, they give it to the fruits and the animals , of which they feed and thus, magically end up on our tables and in our body. From the health point of view, many studies have shown that the accumulation of these substances in the human body can favor spontaneous abortions, alter fertility, cause testicular, thyroid and kidney cancer. What are the means available today to defend ourselves from the sneaky pollution of the Pfas? At present there are not many: we can count on active carbon filters in which the porosity of the filtering carbon has shown a certain effectiveness in intercepting the Pfas, but it is not an effective system on all molecules. But once again, biochemistry could give us an answer to the problem as a team of American researchers has discovered a bacterium, called Acidimicrobium A6 , which would have the characteristic of breaking the bond between fluorine and carbon in Pfas. The bacterium was discovered in an American swamp and studied for a long time as a result of its ability to split ammonium, exploiting the iron present in the soil, without using oxygen. This named reaction, Feammox , was reproduced in the laboratory, after cultivating new strains of bacteria and subjecting the new families to other tests relating to the substances present in the waste water. After 100 days of cultivation in waters containing, among others, also the Pfas, it was noticed that the bacterium had the ability to break down the two main binders, fluorine and carbon, reducing them by 60%. The discovery could be interesting, not only in the liquid contaminated by Pfas, but also in the soils because the bacterium acts in hypoxic conditions, that is of poor oxygen.
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Synthesis and Characterization of Biodegradable Polyesters: Innovative Solutions for the Future of MedicineRevolutionary Materials for Biomedical Applications: An In-Depth Analysis of Biodegradable PolyestersBy Marco ArezioIn recent years, biodegradable polyesters have emerged as one of the most promising solutions in the medical field. Thanks to their ability to degrade in a controlled and safe manner within the body, these materials are revolutionizing areas such as tissue engineering, drug delivery systems, and surgical implants. This article delves into the synthesis processes, characterization techniques, and key applications of these polymers, while also highlighting challenges and future opportunities in the field.An Introduction to Biodegradable PolyestersBiodegradable polyesters are a class of synthetic and semi-synthetic polymers capable of breaking down into harmless products through biological processes. These properties make them particularly suitable for biomedical applications, where the safe disposal of materials is crucial. Among the most studied polyesters are polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), and copolymers derived from these molecules.Interest in these materials has grown significantly with the evolution of materials science and polymer chemistry. Biodegradable polyesters are not only biocompatible but can also be tailored to meet specific medical needs, making them a versatile and innovative choice.How Biodegradable Polyesters Are Created: Synthesis MethodsThe synthesis of biodegradable polyesters can be achieved through various techniques, each with unique characteristics that make them suitable for specific applications. Among the most common methods are:- Condensation polymerization, a process where diols and organic diacids react to form polymer chains. The removal of by-products such as water or alcohol is essential to achieve high molecular weight materials.- Ring-opening polymerization (ROP), a widely used technique for polyesters like PLA and PCL. This method uses cyclic monomers that, under the action of catalysts, open and link to form long polymer chains.- Enzymatic synthesis, an innovative and sustainable approach that employs enzymes such as lipases to facilitate polymerization under milder conditions, reducing the need for potentially harmful chemical catalysts.Characterizing Polyesters to Understand Their BehaviorTo ensure the effectiveness of biodegradable polyesters in medical applications, it is essential to thoroughly analyze their properties. Various techniques are employed to characterize these materials:- Thermal analyses, such as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), are used to study thermal transitions and polymer stability.- Spectroscopic techniques, including FTIR and NMR, are crucial for identifying functional groups and analyzing chemical structures.- Scanning electron microscopy (SEM) allows observation of surface morphology and degradation-induced changes.- Mechanical testing, finally, assesses material performance in terms of strength and flexibility, critical factors for applications like sutures and scaffolds.Applications of Polyesters in MedicineThe versatility and biocompatibility of biodegradable polyesters make them ideal candidates for various biomedical applications. Examples include:- Drug delivery systems, where polyesters like PLA and PLGA are used to create microspheres or matrices capable of releasing drugs in a controlled manner, improving therapeutic effectiveness.- Tissue engineering, with three-dimensional scaffolds that support tissue regeneration thanks to their porous and customizable structure.- Biodegradable sutures and implants, widely used in surgery for their ability to gradually dissolve without requiring removal.Challenges and Future OpportunitiesDespite the progress made, the field of biodegradable polyesters faces several challenges. The primary issue concerns precise control over the degradation rate, which must be adapted to specific application needs. Additionally, ensuring immunological compatibility and developing sustainable, scalable production methods are crucial.The future, however, holds great promise. Advanced technologies such as 3D printing and the integration of “smart” polymers capable of responding to external stimuli are already opening up new possibilities in the biomedical field.ConclusionBiodegradable polyesters represent a cornerstone in the development of innovative solutions for medical applications. With their unique characteristics and customizability, these materials offer vast potential to improve healthcare quality and reduce the environmental impact of medical devices. Further research and innovations will be essential to overcome current challenges and maximize the benefits of these extraordinary polymers.Keywords: biodegradable polyesters, biomedical materials, PLA, tissue engineering, controlled drug release, medical innovation.© Reproduction Prohibited
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Packaging Corrugated Cardboard: Dimensions and Direction of the FibersThe quality and resistance of a corrugated cardboard for packaging depends on the correct arrangement of the fibers and their size How many times have we received, delivered at home, the products we bought on the internet enclosed in a box of cardboard, how many times in our company we use boxes, more or less large, to pack our products for sale, how many times we order by putting our things in cardboard boxes. A type of convenient packaging, simple to use, long-lasting and also circular, as we easily handle corrugated cardboard boxes made with mainly recycled and recyclable paper. In a more professional environment, therefore in the company, the quality of the packaging, whatever they may be, is of substantial importance, not only to present our products to customers, but to protect them during transport and storage in the warehouse. How is recycled corrugated cardboard produced? To create the finished product we start from its origin, so let's see how the sheets that will make up the recycled corrugated cardboard are made >, taking a step back to the paper mill. In fact, it is there where the story begins, using, as raw material, the cardboard that comes from separate collection, which makes up the preeminent part of the recipe, then adding a small part of virgin paper fibers, to increase the quality of the finished product. The type of recipe described does not exhaust the possibilities of finding other blends, as a corrugated cardboard can also be produced 100% with recycled material or with lower percentages of it. Once the raw material has been inserted into the processing plant, water and other substances suitable for the treatment are added, thus starting a mixing of the raw material which leads to the creation of a fluid paste, in which we find an element of crucial importance for the quality of the future finished product which is fibers. In fact, both the recycled cardboard and the natural raw material, which comes from trees, contain different types and form the backbone of future boxes in corrugated cardboard. Once the paper pulp is made, it is spread out, in thin layers, which vary according to commercial requests, on work surfaces to then be sent to the drying of the sheets. Once the correct drying has been achieved, the flat sheets are placed between a corrugated one, specially made through the use of a mechanical folding action assisted by steam. The various layers will then be glued together using vegetable glues derived from potato starch or corn starch. How the direction of the fibers is formed and why it is so important During the creation of the pasta, the most important game regarding future quality is played through the movement of the machine and the presence of water of the cardboard, in fact, with this operation the direction of the fibers is formed which, together with their length, will determine the qualitative result of the product. The fibers are, as mentioned, an armor for the sheet of paper or cardboard, the bearing tool of the product and, their arrangement determines their one-way or two-way mechanical strength. In fact if the fibers are oriented in a parallel way it is possible to tear the sheet in the direction of the same, but it is difficult and irregular in the opposite direction. Furthermore, if the fibers do not have a parallel pattern but unevenly distributed, the mechanical resistance is obtained in both directions of tearing. This does not only apply to the division of the two flaps of the cardboard or paper, but also to its ability to be folded, in fact if we do not consider the arrangement of the fibers, during the folding of a wing of the box, for example, this will be imperfect and difficult, both manually and using the packing machines. What are the differences between using long fibers and short fibers Not all fibers are the same: there are those that are thinner, longer, more irregular, very porous, not porous at all, with knots, of pointed or cylindrical shape and many others. To simplify, with regard to which fiber would be better to use to produce a corrugated cardboard box, we can say that long fibers are the ones most suitable for purpose, as they have greater resistance and hardness, having to create a surface that is as rigid as possible. For completeness we can indicate the short fibers are an excellent solution for creating soft and yielding papers, which are used for multiple uses. Using recycled paper to produce recycled cardboard As we have seen, a good quality paper for making packaging boxes must use a pulp that contains a sufficient amount of fibers long to reinforce the structure. In order to arrive at the correct recipe, to contain costs and to contribute to the use of paper and cardboard waste that we produce every day, the production uses a good part of recycled cardboard. The recycling operations involve, over time, a certain leaching of the fibers, with the consequence that their contribution in the recipe for the production of packaging cardboard, with the various treatment cycles, could decrease. In this case it becomes necessary to resort to the addition of virgin fibers in order to balance the decrease caused by recycling. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Regulation (EU) 2023/2055: New Rules for Those Who Produce, Distribute, or Use Plastic Pellets, Flakes, and PowdersThe New European Regulation on Microplastics Changes How Plastic Companies Must Manage the Production, Use, and Transport of Pellets, Flakes, and Powdersby Marco ArezioWith the adoption of Regulation (EU) 2023/2055, the European Union has introduced one of the most significant measures in recent years in the fight against microplastic pollution. The regulation amends Annex XVII of the REACH Regulation, adding a restriction that directly affects all operators involved in the production, distribution, or use of plastic pellets, flakes, and powders.Its goal is to prevent the accidental release of microplastic particles into the environment and to improve traceability along the industrial supply chain. This represents a crucial step toward the sustainability of the plastics sector, as it is the first time that direct responsibility is assigned to those who handle or transform polymers in granular or powdered form.Starting in 2025, the regulation will become fully operational, introducing concrete obligations for information, prevention, control, and data communication to European authorities.What the Microplastics Restriction ProvidesThe regulation defines synthetic polymer microparticles as falling within its scope when they are smaller than 5 millimeters and contain at least 1% solid polymer content.Included are spherical particles, flakes, and powders resulting from plastic material production, cutting, or grinding processes.The objective is to reduce microplastic emissions—both intentional (such as those added to cosmetic or abrasive products) and unintentional, generated during the industrial handling of pellets or production scraps.Companies will therefore need to adopt technical and organizational measures to minimize material losses and document every stage of the process to ensure transparency of information shared with customers and competent authorities.Who Is Involved in the Plastics Supply ChainRegulation (EU) 2023/2055 applies to all operators in the plastics value chain, regardless of company size or specific role in the production process.- Manufacturers of plastic pellets, flakes, or powders: must provide customers with clear instructions for use and disposal, indicating any risks of dispersion.- Industrial users (converters, compounders, molders, recyclers): must collect data on quantities used, estimate environmental losses, and report annually to the European Chemicals Agency (ECHA).- Distributors and importers: must ensure that all supplies are accompanied by the proper documentation and comply with the requirements of the regulation.- Transporters and logistics operators: must adopt safe handling practices to prevent losses during transport or storage.The entire value chain will thus be subject to new forms of shared responsibility, with particular focus on the traceability of plastic materials throughout every stage of their operational cycle.Obligations, Deadlines, and New Operational ProceduresThe regulation provides a series of progressive deadlines. From October 17, 2025, suppliers of microparticles will be required to provide customers with specific information on the quantity, composition, and handling of plastics in granular or powdered form.They must also include a standard declaration indicating compliance with Regulation (EU) 2023/2055.Starting in 2026, the annual reporting obligation to ECHA will come into effect, requiring the collection and transmission of data on:- quantities of microplastics produced or used- types of polymers employed- estimated environmental losses- mitigation measures adoptedThe goal is to establish a European monitoring system for the management of plastic microparticles, capable of identifying operational weaknesses and progressively reducing unintentional emissions.How to Prevent Pellet and Powder LossesTo comply with the regulation, companies will need to adopt a systematic approach to loss prevention. The most critical areas include material loading and unloading, storage, silo cleaning, and internal handling.Among the most effective measures are:- installation of containment and collection systems during material handling- personnel training on proper material management- use of closed systems for pneumatic pellet transport- preparation of emergency procedures for accidental releases- installation of filters and barriers at discharge points to prevent release into sewer networksThe implementation of these practices will soon become an essential requirement under the forthcoming EU Regulation on Pellet Loss, currently under discussion.Economic and Managerial Impacts for CompaniesCompliance with Regulation 2023/2055 entails a significant transformation in the management of industrial activities.Companies will need to invest in control systems, data collection, and monitoring technologies—initial costs that may be offset over time by greater operational efficiency and reduced environmental risks.The main consequences include:- increased technical documentation requirements for customers and authorities- the need for periodic internal audits and, in the future, certifications from third-party bodies- greater contractual responsibility toward suppliers and transporters- competitive opportunities for those demonstrating early compliance and sustainable material managementIn the long term, the most forward-thinking companies will be able to leverage compliance as an asset for environmental reputation and commercial advantage, especially in sectors that prioritize transparency and ESG sustainability.Roadmap for ComplianceTo manage the regulatory transition effectively, companies can follow a five-step operational roadmap:- Initial analysis (gap analysis) – Map pellet usage and handling points, assess risk areas, and review available data- Data collection and loss estimation – Identify emission sources, install measurement systems, and establish control logs- Technical documentation – Draft the required declarations, labels, safety data sheets, and operating instructions- Plant and training adaptation – Upgrade containment systems and train staff on new procedures- Continuous auditing and monitoring – Periodically verify compliance, update reports, and improve environmental performanceThis step-by-step plan allows companies to manage regulatory complexity without interrupting production activities and to prevent potential future non-compliance.Toward Responsible and Traceable PlasticsRegulation (EU) 2023/2055 represents a paradigm shift for the plastics sector: from a production-centered approach to one based on integrated environmental responsibility.The focus is no longer limited to the transformation or recycling phases but extends to the entire life cycle of materials—including process scraps and fine dust from manufacturing.For companies, this means developing an industrial model grounded in prevention, traceability, and transparency, principles aligned with the foundations of the circular economy.Those who can anticipate these changes will turn a regulatory obligation into a strategic opportunity: to reduce losses, improve efficiency, and strengthen market trust in a cleaner, more controlled, and sustainable plastics industry.© All rights reserved – Reproduction prohibited
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How to Choose an Odor-Free Recycled Blow Molding HDPE for AutomotiveHow to Choose an Odor-Free Recycled Blow Molding HDPE for AutomotiveThe use of recycled HDPE for blow molding is multiplying in companies that, until a few years ago, denied recycled material, brandishing it as a waste, a waste, of poor quality techniques, aesthetics and images. Fortunately, many things have changed inside and outside companies, so that recycled blow molding HDPE has passed within a few years from an outcast to a product of great interest, both practical and in the media. Without a doubt there have also been significant technical improvements on the plants that characterize the recycling production chain, so much so that many of the classic problems encountered in the use of HDPE recycled during the production of blown articles, have been partially resolved. A different approach has also been achieved by both the purchaser of the raw material and the final consumer, who have lost the criticality related to an article made with recycled material. But in the field of recycling there are still streams of HDPE that can present qualitative, aesthetic and odor problems. In relation to the odor contained in the bottles to be recycled, post-consumer raw material used for the production of the blow molding granule, certainly the most persistent is the one that derives from detergents, in fact, despite washing the bottles to be recycled, even carefully, the surfactant odor remains almost indelibly. If in the packaging sector the residual smell of detergent is increasingly tolerated, but in other sectors, such as the automotive one, it is a strong discriminant. With a view to the circular economy, the use of post-consumer recycled HDPE granules has become a real need for the environment, as it is essential to reuse plastic as much as possible at the end of its life, to avoid it ending up in waste. On the market there are neutral or opaque HDPE granules, which do not have inside them odors of detergent, food or other fragrances (or stinks), thus making them suitable for more professional use. For example the air ducts in the automotive sector, can be made with recycled HDPE granules, but they must not attribute to the air that passes inside them , unpleasant or persistent odors. The input of these granules consists of a mono plastic (HDPE only) which does not come into contact with other waste and therefore does not absorb any, during the cycle of storage, transport in bags and final recycling, the classic contaminations that give rise to the pungent and persistent odors of separate waste collection. With these materials, neutral or opaque, you can blow air vents, or other parts in the automotive sector, which do not have odors on the finished product, succeeding to combine quality, circularity and technical requirements. In any case, the incoming granules can be tested through a simple analysis on the footprint of the contained odors, through an ion mobility gas chromatography test, that in just 20 minutes can give us a photograph of the chemical components of the granules, in relation to possible odors during the blowing phases of the article or once placed in the vehicle. These data released by the test are not empirical, like the test done with the nose by a group of people, but they are completely analytical, precise and irrefutable.See more information on the topic Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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How to Improve the Molding of Non-Aesthetic Plastic ItemsConsiderations for the production and use of PO (PP/PE) granuleNon-aesthetic finished products, mainly intended for the market disposable, they were normally made with polypropylene compound, made up of a mixture of PP and PE (polypropylene + polyethylene) coming from the granulation of waste from separate collection. If we consider plastic pallets or spacers for rebar or fruit and vegetable crates, to give just a few examples, the mix between the two families of polymersmade it possible to produce compounds whose percentage of PP in the mixture could vary from 30-40% to 60-70%, depending on the envisaged recipe. The melting index at 230°/2.16 kg. it varied from 3 to 6 if the product had no added mineral fillers. The characteristics of the granule produced and, consequently of the final product, express a good performance with regards to resistance to compression and a less excellent in terms of flexural strength. As regards the ability to receive the colors in the extrusion phase of the granule or during the molding phases of the final product, yes may note that the medium-dark color range is the most appropriate, also by virtue of the fact that the base of the post-consumer semi-finished product to be transformed into granules is usually dark grey. Today the PO, which identifies the polyolefin mixture coming from separate waste collection, has taken on a different composition compared to the past due to the greater performance of municipal waste separate collection systems, which tend to maximize the removal of the polypropylene fraction from the PP/PE mix. This happens because the demand for polymers on the market tends to favor single compounds whether they are PP or HDPE or LDPE. The production trend described above involves having to work on a PP/PE mix which is qualitatively less performing than in the past, because they have been the balance between the three families, PP, HD, and LD which constituted the PO in the past has been altered. Furthermore, the increase in the production of both the waste to be processed and the demand for a granule from PP/PE compound has pushed some plastic waste treatment plants to accelerate the washing phase to recover productivity, decreasing the quality of the densified and ground material needed to produce the granule. We can list some critical issues in the production of PO compounds: • increase in LD% at the expense of HD in the polyolefin mix • worsening of the quality of the incoming wash due to the increase in volumes to be treated and the different % of polymers in the recipe • increase in the presence of bioplastics within the selected fraction which causes problems in the quality of the granule • increase in the use on the market of packaging made with mixed plastics involving a greater percentage of multilayer materials, such as some labels, which difficult to coexist with traditional PO . Compared to these changes in the basic composition of the PO and its processing , we will have to face problems to manage in the granule production phase and in the molding phase, in order to minimize the negative impacts of the quality of which the granule is composed. Regarding production, action should be taken: • on washing and drying times of the semi-finished product • on the size of the washing tanks • on water management (cleaning and replacement) • on the recipe of the PO compound for granulation • on filtration As regards the molding phase, the following should be done: • on machine temperatures • on the granule drying phase • on verifying mold cooling The technical intervention on these critical issues leads to the following improvements: • greater resistance to bending of the final product • improvement of aesthetic surfaces with reduction or disappearance of flashing on the finished product • improvement of color homogeneity • reduction of the bad odor of the granule and the finished product • increase in the life of screws and cylinders in the granulation phase and in injection molds • healthier workplaces during the plastic melting phases
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Bisphenol A in Food Packaging: the EFSA OpinionBisphenol A in Food Packaging: the EFSA OpinionAs we have already dealt with in the article "Polymeric coatings for metal food packaging" the massive use of pre-packaged food products, whether they are with metal, plastic or of other materials, raises the question of possible chemical substances, potentially dangerous for human health, that could be generated inside the package. Some of these substances can be generated by the transferring effect of the packaging materials towards the food, others concern the release of chemical substances that are generated by the food itself due to the packaging. Indeed, the European Food Safety Authority (EFSA) has reviewed the risks of Bisphenol A (BPA) in food by proposing to significantly lower the Tolerable Daily Intake (TDI) compared to that of its previous assessment in 2015. EFSA's new conclusions on BPA are set out in a draft scientific opinion available for public consultation until 22 February 2022. All interested parties are invited to participate. The TDI is the estimate of the quantity of a substance (expressed in relation to body weight in kg) that can be ingested daily throughout one's existence without worthy risks of note. In its 2015 BPA risk assessment, EFSA established a temporary TDI of 4 micrograms per kilogram of body weight per day. In its draft BPA from scratch, published today, EFSA's Expert Group on Food Contact Materials, Enzymes and Processing Aids (CEP group) established a TDI of 0.04 nanograms per kilogram of body weight per day. The lowering of the TDI is the result of the evaluation of studies that appeared in the literature from 2013 to 2018, in particular those that highlight adverse effects of BPA on the immune system: in animal studies an increase in the number of "T-helper" cells has been observed, a type of white blood cell which plays a fundamental role in cellular immune mechanisms and which, if increased, can lead to the development of allergic lung inflammation. Comparing the new TDI with estimates of consumer exposure to BPA via diet, EFSA concludes that both medium and high exposure to BPAs outperform the new TDI in all age groups, thus giving rise to health concerns. A systematic approach The dr. Claude Lambré, president of the CEP group, said: "This updated draft is the result of a careful evaluation lasting several years. We have applied a systematic approach to select and evaluate the available evidence. The new scientific studies appearing in the literature have helped us to address important elements of uncertainty about the toxicity of BPA." EFSA already assessed the safety of BPA for food contact materials in 2006 and 2015. Back then its experts only managed to establish one Temporary DGT due to some elements of uncertainty, underlining the need to fill the gaps found in the data. Automatic translation. We apologize for any inaccuracies. Original article in Italian. Source: EFSA
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The Modern Active Packaging with Millennial RootsStudying how the packaging interacts with the product contained, how time, structure and chemistry make this relationship evolveThe current active packaging is well defined by the EC regulation 450/2009 which states: "... active materials and objects intended to come into contact with food products are materials and objects intended to extend the shelf life or maintain or improve the conditions of packaged food products. They are designed to deliberately incorporate components that release substances into, or absorb into, the packaged food product or its environment ”.It seems to be a conquest of our times to better preserve the products inside the packaging, whether they are food or other products, making them, at times, interact with the packaging that contain them.This means worrying and studying how the packaging interacts with the product contained, how time, structure and chemistry make this relationship evolve, finally verifying the pros and cons, on the product that will be used.In reality, the problem has already been addressed in some way over the past millennia, even without having the multiple packaging available today.There was no plastic, aluminum, Tetra Pack, but wood, glass and ceramic yes, and above all through the wooden barrels, our predecessors sensed that the barrel had a close relationship with the final quality of the wine.In fact, they realized that the fine wood barrels yielded polyphenolic substances to wines and spirits that improved the color, flavor and aroma of the product.Today, with the increase in the types of packaging available to us, the problems that we must consider and solve in order to control adverse reactions between packaging and product and encourage positive ones have also multiplied.Among those unwanted or harmful we can list:Humidity. This favors the proliferation of molds and bacteria in some cases, while in others it is necessary to control the aerobic respiration of plants and microorganisms. For these reasons it is necessary to act in order to be able to control the development of humidity in the packages based on the type of product contained. To do this, it is possible to use bags containing silica gel, calcium chloride and calcium oxide, or multilayer materials containing hygroscopic compounds, such as Pitchit film.Oxygen. Everyone knows that the presence of oxygen facilitates the reduction of the shelf life of stored food products as a result of reactions (chemical and enzymatic oxidations, degradation of pigments and aromas) and metabolisms (aerobic respiration, proliferation of aerobic bacteria, molds and yeasts). A widely used system is the preservation of food through vacuum packing, but there are other methods, such as sachets that absorb oxygen, consisting of small elements that, through a chemical reaction between metallic Fe and O2, reduce its presence inside. of the packaging. This methodology is not applicable to all packaging as the chemical reaction is triggered in the presence of a certain degree of humidity and the presence of iron can interfere with the automated logistics systems in the presence of metal detectors.Ethylene. Ethylene is a plant hormone that influences the aerobic process and the ripening of many fruits, therefore its reduction produces a slowdown in the ripening of the product. Substances capable of adsorbing ethylene, such as activated carbon, silica gel and zeolites, can be included in the packaging.Volatile compounds deriving from the degradation of food. Especially the lipid and protein degradation of food produces volatile substances with an unpleasant smell. Volatile aldehydes (hexanal, nonanal, etc.) produced during the oxidation of unsaturated lipids, can be intercepted by chemical compounds inserted in polyolefin copolymers (PE / PP). There are other chemicals, such as hydrogen sulfide (H2S) and volatile mercaptans (R-SH), which are generated by protein degradation, can be sequestered with specific adsorbents.Then there are protective and improving substances that interact with the products contained in the packaging. Taking a quick rundown we can mention:Antioxidants. Contained in the plastic materials intended for packaging production favor a protective action over time. There are also natural antioxidants, such as α-tocopherol, which is added in the production of specific packaging films.Natural Antimicrobials. They are substances responsible for controlling microbial proliferation in food that interact with the humidity and temperature inside the packaging in contact with the fresh product.Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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PMMA or Recycled Polymethylmethacrylate: Where does it Come from and What is It?PMMA characteristics, processes, applications and recycling systems PMMA, or Polymethylmethacrylate, is a thermoplastic resin belonging to the group of technopolymers, obtained from the polymerization of methacrylate (MMA). It is commonly considered an acrylic glass, as it boasts a better transparency than traditional glass, so much so that in many applications it has been replaced by PMMA. The history of PMMA began in 1938 when in Germany, by Otto Rohm, the first product called plexiglass was placed on the market. As we said, it has the evident characteristic of transparency, but it can maintain, unlike glass, also an excellent mechanical resistance, which is achieved thanks to different polymeric compounds, so much so that it is also used for the production of safety glass. What are the characteristics of PMMA • density: 1.18 - 1.19 gr / cm3 • melting temperature Tm: 105-160 ° C • glass transition temperature Tg: 80-105 ° C • good rigidity • mechanical strength • high impact resistance and hardness. • good tensile strength • good compression and bending values • high UV stability • excellent resistance to aging • sensitivity to scratches and abrasions • good weather resistance • excellent optical properties, clarity and transparency • excellent electrical properties • good thermal resistance • chemical resistance to salts • resistance to aliphatic hydrocarbons • does not resist chlorinated hydrocarbons, concentrated acids, nitro and paints How PMMA works Polymethylmethacrylate can be processed through extrusion and thermoforming, which represent two processing systems for traditional plastics. There is a third one, called by pouring, which is normally used for the production of PMMA sheets, using an acrylic paste, called "syrup", obtained pre -polymerizing the MMA monomer in a reactor by stirring. PMMA Applications Polymethylmethacrylate has a very wide range of applications, in different sectors and with countless products that we could summarize below: Construction sheets for doors and windows unbreakable windows skylights bathtubs shower trays shower enclosures cabins for medical use in general elements of pools sinks honeycomb sheets for greenhouses Lighting outdoor luminous signs traffic signs advertising plates bright letters illuminated plaques for instructions Transport sector car lights reflectors speedometer discs warning triangles flashing lights windshield for aircraft and space uses Medical sector filters parts of dialysis equipment containers for blood orthopedic applications dental prostheses cosmetic packaging lenses Electrical and electronics industry switches command buttons optical memorizers CD and DVD displays for mobile fiber optic elements How to recycle PMMA The recycling of Polymethylmethacrylate begins with the collection and selection of end-of-life products or scraps of industrial processes, differentiating them according to the color so to create homogeneous sources between them. At this point there are two recycling systems: the mechanical one, like a normal polyolefin, and the chemical one, which aims at the depolymerization of PMMA. Using mechanical recycling, the material to be recycled is ground into suitable dimensions for subsequent use and reintroduced into production, for example slabs, through the thermal process induced by an extruder. Using chemical recycling, the PMMA waste will undergo a depolymerization process, which consists in the dissociation of the molecules of the material to be recycled. After appropriate purification, MMA is generated, which, through a polymerization reaction, gives life to the new 99% pure rPMMA polymer. The cycle is completely zero impact, as the process is carried out in a closed circuit and all the by-products of this chemical process are reused within the production cycle . The disadvantage of chemical recycling is that at the end of the process there will be a less translucent rPMMA, having a high recycling cost and an important energy consumption. Common trade names for PMMA Acridite ACRYLITE Acryvill Altuglas Amanite Cyrolite Green Cast LuciteOptix Oroglas Perspex Plexiglas R-Cast Setacryl Crylux TrespexZylar Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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PVC Films for Food: What Contaminations Are Possible?For many years, food can be portioned through a packaging consisting of a PVC film It is by now it is our habit to buy portions of food that the shopkeeper or large-scale distribution packs in a PVC film. Even in our homes, partial batches of food are commonly wrapped in these films to increase shelf life and safeguard quality. Although there are also several PE films today, the PVC market is still the most important due to numerous techno-economic factors. The use of PVC polymer allows to create a very resistant film, with a low permeability to water and oxygen, with a good resistance to acids and diluted alkalis. Moreover, for a completely practical fact, the PVC food films have an excellent packaging capacity, easily welded to a plate or bowl or on itself. same. From an economic point of view, the presence of chlorine in the PVC compound, essential for its chemical structure, significantly reduces the cost of the finished product. because there is an ethylene saving of about 50% compared to the use of PE for the same product. Using PVC it is possible to insert a series of additives that can modify its performance characteristics, having the possibility of creating, with a single polymer, different products. Let's see the main additives that are used in the packaging industry: • Anti-blocking agents: reduce the tendency to adhesiveness • Anti-fog agents: promote the formation of a homogeneous and continuous veil of liquid • Antimicrobials: prevent the growth of microorganisms • Antioxidants: They prevent the degradation of the film due to the atmosphere • Antistatic: They reduce the accumulation of electrical charges that attract dust • Swelling agents: used to produce foams from plastic materials • Catalysts: they start the polymerization in the production of plastic resins • Dyes: allow the coloring of the films • Coupling agents: favor the coupling between pigments and polymers • Flame retardants: reduce the flammability of materials that are combustible • Heat stabilizers: reduce the degradation of PVC into hydrochloric acid • Lubricants: Reduce adhesiveness between PVC and metal parts • Plasticizers: improve flexibility, workability and expandability All these additives, but especially the plasticizers, are subject to very strict regulations to allow their use in the food sector. It must be considered that there are about 300 types of plasticizers on the market and those approved for food use, are subject to the hygiene regulations of packaging, containers, utensils intended to come into contact with food substances or substances for personal use. The substances that could transfer from the packaging to the food can be divided into three categories: • Added substances: mainly represented by the PVC additives listed above • Residues: represent parts of polymeric material with incomplete reactions (monomers, catalysts, solvents, adhesives, etc.) • Newly formed products: these are substances that originate from the spontaneous decomposition of materials or during operations of transformation into an artifact These substances, defined as neoformations, are very variable among themselves, depending on many chemical-physical factors that can occur and that can affect the possible transfer of substances in the food that are difficult to manage and resolve. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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How to Verify Recycled Content in Plastic: The New Technology That Could Change European PackagingHow Is the Percentage of Recycled Plastic in Products Really Measured: ISO Standards, European Rules, Supply Chain Audits, Mass Balance and Digital Watermarks in the New EU Packaging LandscapeAuthor: Marco Arezio. Expert in the circular economy, polymer recycling and industrial plastics processing. Founder of the rMIX platform, dedicated to enhancing the value of recycled materials and developing sustainable supply chains.Date: March 26, 2026Reading time: 16 minutesIntroductionSaying that a package “contains recycled plastic” is easy. Proving it in a serious, repeatable and defensible way before customers, authorities, auditors and the market is much more difficult. And today this difference matters more than before, because plastic is at the center of Europe’s new circularity policies: packaging accounts for about 40% of the plastic used in the Union and, in 2022, each European citizen generated 186.5 kg of packaging waste. The new European Packaging and Packaging Waste Regulation, the PPWR, entered into force on February 11, 2025, and its general date of application is set for August 12, 2026; among its objectives are increasing the safe use of recycled plastic and ensuring the recyclability of all packaging by 2030.The real question, therefore, is not only how much recycled plastic is in a product, but how it is actually proven. The correct answer is less intuitive than it may seem: in most cases, the percentage of recycled content cannot be read “by eye” nor certified with a single laboratory test on the finished item. Instead, it is built through a combination of regulatory definitions, mass balances, supply chain traceability, volume reconciliation, third-party audits and, increasingly, digital tools that improve the separation and qualification of incoming waste.What “recycled content” really meansThe technical basis starts with the definition. In the ISO field, recycled content is defined as the proportion, by mass, of recycled material present in a product. ISO 14021 remains one of the key references today for self-declared environmental claims and also includes the terms related to “pre-consumer material” and “post-consumer material,” that is, the distinction between material recovered before use by the final consumer and material coming from post-consumer waste.This point is decisive, because many market ambiguities arise here. A producer may declare 30% recycled content, but it is necessary to understand whether that 30% comes from internal or external industrial scrap, from urban post-consumer waste, from selected commercial waste, or from a combination of the two. From the point of view of environmental communication, the difference is not secondary: the technical quality of the material, the circular value of the claim and its market perception change significantly depending on the origin of the recycled content. ISO 14021 provides precisely this terminological and methodological framework to avoid vague or misleading claims.How the percentage of recycled plastic is calculatedThe basic principle is simple: it is a mass ratio. In the most straightforward case, the percentage of recycled content corresponds to the mass of recycled plastic incorporated into the product divided by the total mass of plastic considered within the scope of the claim, multiplied by 100. For single-use plastic bottles, the European Commission has already set specific rules: Implementing Decision 2023/2683 establishes that the proportion of recycled plastic is calculated by dividing the weight of recycled plastic in the bottles placed on the market by the total weight of the bottles placed on the market.But the formula alone is not enough. It is necessary to define the calculation perimeter precisely: batch, line, plant, annual period, product category, specific packaging family. It is also necessary to know which process losses were considered, which additives or masterbatches enter the formulation, and how the quantities coming in and going out are reconciled. Audit schemes based on EN 15343 and the most widely used traceability certifications require exactly this: documentary evidence, identification of flows and a plausibility check between inputs, yields, losses and declared output.Why the laboratory is almost never enoughHere we enter the heart of the problem. In theory, the laboratory is essential to identify the polymer, measure impurities, assess contaminants, verify MFI, ash, density, migration, odors or stability. In practice, however, the laboratory is almost never sufficient, on its own, to certify the exact percentage of recycled plastic contained in a finished product. The European Commission itself, in the section dedicated to the recycling of plastics intended for food contact, explains that the composition of recycled plastic cannot easily be subjected to official controls as happens with virgin plastic and that, precisely for this reason, controls focus on the production of recycled material and on audits of installations.The same approach also emerges from the technical literature of the European JRC in other highly regulated sectors: the verification of the content of recycled materials is described as based exclusively on documentation, with calculation rules, blending rules and measurement points defined upstream. In other words, the laboratory serves to qualify the material; the declared percentage, on the other hand, is demonstrated above all through chain of custody. This is an essential distinction for understanding why so many commercial declarations prove fragile when a robust traceability structure is missing.European traceability: EN 15343 as the cornerstoneIn the European context, EN 15343 is the cornerstone standard for recycled plastic. The standard specifies the procedures necessary for the traceability of recycled plastics and provides the basis for calculating the recycled content of a product. This means that the declared percentage does not arise from a qualitative perception of the material, but from a documented supply chain: origin of the waste, transformation, batch identification, internal controls, volume reconciliation and consistency between inputs and outputs.The certification schemes applied by the market move in exactly this direction. RecyClass, for example, explicitly states that its traceability certification verifies the exact percentage of recycled content through a controlled blending approach aligned with EN 15343 and ISO 22095; it also предусматриes third-party on-site audits and annual renewal of the certificate. This is important because it distinguishes a simple commercial self-declaration from an audited and defensible declaration.Mechanical recycling: the clearest case, but not a trivial oneIn mechanical recycling, the measurement of recycled content is generally more straightforward than in other scenarios. The recycled material enters as ground material, flakes or pellets; it is mixed with possible virgin material, additives or colorants; then it is transformed into the final product. In this case, the percentage can be demonstrated through a combination of purchase documents, supplier certificates, production sheets, compound recipes, mass balances and checks on the quantities actually processed, taking losses into account. Process audits require precisely a reconciliation of volumes to verify that the output corresponds to the recycled input used, considering yields, losses and additives.However, risks also exist here. If the incoming recycled material is not itself traceable or if it comes from poorly qualified heterogeneous streams, the numerical percentage may be correct on paper but weak in substantive terms. In other words, “50% recycled content” does not always have the same value: it matters whether it is truly traceable post-consumer PCR, pre-consumer industrial scrap, food-grade material, or a mixed stream with high qualitative uncertainty. For this reason, the strongest companies do not limit themselves to weighing the material, but document the origin and quality of the recycled content used.Food contact: when proof shifts even more toward the processIn food packaging, the issue becomes more rigorous. The European Commission points out that, when plastic is recycled for food-contact use, the problem is not only quantifying the recycled content but ensuring that any chemical contaminants have been removed to safe levels. Precisely because such contaminants may be unknown or variable, official control focuses not so much on the analysis of the finished product as on the decontamination process, good manufacturing practices and plant audits.This is also a crucial point for marketing communication. If a food container declares a certain recycled content, the credibility of that declaration depends not only on the numerical percentage, but on the ability to demonstrate that the recycled content was obtained within an authorized, monitored process suitable for the intended use. In food packaging, therefore, the “how much” and the “how” cannot be separated.Chemical recycling and mass balance: the most delicate issueWhen chemical recycling is involved, the matter becomes more complex because plastic waste is transformed into feedstock that is mixed with conventional raw materials in complex industrial systems. In these cases, the physical segregation of the “recycled” atom is not realistically practicable throughout the chain. For this reason, mass balance models are used, that is, chain of custody models that allocate a share of recycled content to outputs on the basis of accounting, temporal and allocation rules, without exceeding the quantity of recycled input that actually entered the system. ISCC PLUS describes this approach as one of the chain of custody options, alongside physical segregation and controlled blending.The issue is so central that ISO has also published ISO 22095-2:2026, specifically dedicated to the requirements and guidelines for applying the mass balance model in chain of custody systems. This is an important signal: mass balance is becoming less and less a mere “market” practice and increasingly an area of technical standardization.On the European regulatory level, the matter is still very much open. In July 2025, the Commission launched a consultation on new rules to calculate, verify and report chemically recycled content in single-use plastic beverage bottles. The proposed methodology is based on the fuel-use excluded allocation rule, meaning it excludes from recycled content any share of waste destined for fuels or energy recovery; it also provides for annual third-party verification for the most complex stages of the chemical supply chain and lighter requirements for SMEs. In February 2026, the Commission still indicated that it was in the final stage of defining these rules, not yet consolidated into a definitive and fully operational framework.The new technology that can truly change European packagingWhen people talk about recycled plastic, many imagine that there is a machine capable of taking a finished package, analyzing it and saying with precision: “there is 37% recycled plastic in here.” In industrial reality, that is not how it works today.The technology that can truly change European packaging is not a laboratory test capable of magically reading the recycled content of every package, but a system that helps separate packaging waste better before it is recycled. This system is based on digital watermarks, that is, small invisible or almost invisible codes printed on the package.To understand what this means, let us imagine a plastic tray for food, a detergent bottle and a cosmetic container. Today, when these packages arrive at a sorting plant, automatic systems can identify the type of plastic fairly well, for example PET, HDPE or PP, but they often have more difficulty distinguishing the original use of the package, that is, whether that plastic came from a food, cosmetic or household application. And this difference is very important, because plastics that appear similar may require different recycling pathways.This is where digital watermarks come into play. In practice, every package can carry with it a sort of “digital identity card” that can be read by sorting systems. This identity can tell the plant: “I am a food tray,” “I am a detergent bottle,” “I am a PP package,” “I belong to a certain category.” Thanks to this information, waste can be sorted much more precisely than with traditional systems.This is the real change: recycling is not improved at the end of the process, but at the beginning, when the waste is separated. If you start with a cleaner, more homogeneous and better classified stream, the recycled material obtained at the end will also be better.To make this even more concrete, one can think of the difference between collecting all fruit together in one large bin or separating it immediately by type and quality. If everything is mixed, the final result is a product that is less controllable. If, instead, separation is done properly at the origin, the final result is cleaner, more consistent and more suitable for quality uses. The same thing happens with plastic.This is why this technology is of such great interest to European packaging. Europe’s main problem, in fact, is not only recycling more, but recycling better. Much recycled plastic today has variable quality because it comes from waste streams that are too mixed and difficult to distinguish accurately. If sorting can be improved, the result is a purer, more stable and more reliable PCR, that is, post-consumer recycled plastic.This also has a very important consequence on the regulatory and commercial level. When a company declares that a package contains a certain share of recycled plastic, it must be able to prove it credibly. If the recycled material comes from a cleaner, traceable and well-separated supply chain, that declaration becomes more robust. In other words, digital watermarks are not used to directly “measure” the recycled content of the finished package, but to build a more reliable recycling chain, and therefore to make declared percentages more credible as well.From a practical point of view, their advantage is threefold. First: they help plants distinguish packaging better. Second: they make it possible to produce higher-quality recycled material. Third: they make it easier to connect that recycled material to serious supply chain documentation, useful for audits, certifications and compliance with the new European rules.So the central point is this: the technology does not change European packaging because it reads the recycled content already present in the product, but because it makes smarter, cleaner and more demonstrable recycling possible. And this is exactly what Europe needs today: not only more recycling, but recycling that can withstand technical checks, customer demands and future PPWR rules.What Europe is really asking for todayOn the regulatory front, Europe is moving on two levels. The first is the one already active for single-use plastic bottles: the SUP Directive requires 25% recycled plastic in PET bottles from 2025 and 30% in all plastic beverage bottles from 2030. The European Commission also recalls that in 2023 it adopted Implementing Decision 2023/2683 on the rules for calculating, verifying and reporting recycled content in single-use bottles.The second level is the broader PPWR framework. The official pages of the Commission clarify that the regulation entered into force on February 11, 2025, will generally apply from August 12, 2026, aims to make all packaging recyclable by 2030 and requires plastic packaging to incorporate increasing shares of recycled content with targets for 2030 and 2040. In other words, the verification of recycled content is no longer a niche issue for brands sensitive to sustainability: it is becoming a compliance infrastructure for the European market.How a company should really verify recycled contentIf a producer wants to avoid greenwashing and prepare for the new European context, it should not only ask itself “how much recycled plastic am I using?” but also “how will I be able to prove it in an audit?” The correct answer today is to build a system composed of four elements: a clear definition of the claim according to recognized standards; traceability of incoming material; mass balance with volume reconciliation; independent third-party verification when the market or customer requires it. This approach is consistent with ISO 14021, EN 15343, RecyClass schemes and the logic of European verification rules for bottles and food contact.In practical terms, a robust claim should specify at least three things: whether the recycled content is pre-consumer or post-consumer; which chain of custody model has been applied, that is, segregation, controlled blending or mass balance; which independent body has verified the system, if any. When this information is missing, the declared percentage may even be numerically correct, but it remains weak from an evidentiary point of view.ConclusionThe percentage of recycled plastic in products is not really measured with a single machine and is not demonstrated with an isolated formula. It is verified through an architecture of proof: ISO definitions, European traceability standards, mass balances, plant audits, supply chain documentation and, in the more advanced cases, digital systems that improve the separation and quality of recycled material upstream. This is the point that many commercial communications tend to oversimplify.The new technology that can change European packaging today is therefore not a “magic test” for reading recycled content in the finished item, but a technological ecosystem capable of making the supply chain more intelligent. Digital watermarks are probably the most concrete frontier in this direction, because they can increase sorting quality, create purer PCR streams and make future declarations about recycled content much more credible. In a European market that is moving from narrated sustainability to verified sustainability, this distinction will make the difference between those who communicate and those who prove.FAQHow is recycled content measured in plastic?As a rule, it is measured as the proportion by mass of recycled material in the product, but actual proof comes above all through traceability, mass balances and supply chain audits, not through a single test on the finished product.Is there a laboratory test that can say with certainty how much recycled plastic is in a package?In general terms, no: European sources show that verification of recycled content is based above all on documentation and process control, while final analysis alone is not sufficient to establish the exact declared share in all cases.What is the difference between pre-consumer and post-consumer?Pre-consumer comes from scrap recovered before use by the final consumer; post-consumer, on the other hand, comes from waste generated after use by households or commercial activities. ISO 14021 explicitly distinguishes these categories.What is mass balance in recycled plastic?It is a chain of custody model used above all when recycled and conventional feedstocks are mixed in complex systems, as in chemical recycling. In that case, the recycled share is allocated to outputs according to accounting rules that can be verified.Do digital watermarks measure recycled content?Not directly. However, they improve the separation of packaging waste and the creation of purer, more traceable streams, an essential condition for producing quality recycled material and making verification of recycled content in future products more robust.Real and verified sourcesEuropean Commission, Packaging waste and Packaging & Packaging Waste Regulation (PPWR), with data on entry into force, application date and objectives of the regulation.European Commission, Single-use plastics, with targets on recycled content in bottles and the chronology of implementing acts.European Commission, Plastic Recycling / Food Safety, with clarifications on controls, contaminants and the central role of process audits in food contact.ISO, ISO 14021 and ISO references on chain of custody and mass balance.European standard EN 15343, on the traceability of recycled plastics and the calculation of recycled content.European Commission, 2025 consultation on rules for chemically recycled content in bottles, with the fuel-use excluded method and third-party verification.AIM / HolyGrail 2.0 and HolyGrail 2030, on digital watermark technology and intelligent sorting results.ISCC PLUS and RecyClass, for chain of custody models, controlled blending, mass balance and traceability audits.Image under license© Reproduction Prohibited
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