Post-Consumer Recycled LDPE: 60 Types of Odors Hinder SaleLDPE Recycled from Post-Consumer: 60 Types of Odors Obstruct Sales The separate collection of plastic packaging, especially for those in LDPE , is a modern achievement which allows, through recycling, the reuse of exhausted packaging with the dual advantage of reducing the carbon footprint and the withdrawal of natural resources from the earth to create new products. However, much still needs to be done in the recycling sector as the share of plastic that is collected and reused is still far lower than that which is produced every day. This quantitative imbalance between what is recycled and what is produced again has many causes: • Limited diffusion of separate waste collection in the world • Difficulty in recycling many multilayer plastic packaging • Low quality of recycled raw material • Lack of a recycling culture In countries where separate waste collection has started and functions stably, the production of recycled raw material suffers from a fairly negative judgment on its quality, caused by factors that also depend, but not only, on the mechanical recycling chain. This negative evaluation has a significant impact on the sales of the recycled raw material, relegating its use only to some sectors of use, thus reducing the salable quantities and lowering the average price per ton, which in turn leads to a low economic margin for companies that recycle. Furthermore, the less recycled granules sold , the less plastic waste that can be recycled and the greater the problem of its disposal becomes, risking the precious raw material that could be reused ending up in landfill. Among the problems that recycled raw materials suffer from, despite the enormous plant development in the sector, that of odor is among the most felt by customers who could use it to produce films, rigid packaging, materials for the construction sector, for automotive, gardening, furniture and many other products. To date, the perception of the smell of a post-consumer plastic raw material is entrusted, in a completely empirical way, to a nasal sensation of those who produce it and those who use it, who evaluate in an extremely subjective way both the type and the intensity of odors present in recycled plastic. An evaluation which can then clash with the end customer who will buy the product created and give a further personal evaluation of the smell. The human nose is certainly an excellent tool but each person perceives odorous stimuli in a completely personal way, and this is why, in particular cases, groups of people are hired to together evaluate the odors to be intercepted. If we take the plastics recycling chain as an example, starting from separate waste collection, we have seen that the LDPE bags and flexible packaging that go for recycling bring with them a very high number of chemical substances that generate odors in the recycling chain . The detection of odor sources has not been studied through empirical sensory methods, therefore through the human nose, but through a chemical investigation carried out by a laboratory instrument consisting of a gas chromatograph with an ion mobility spectrometer. This tool analyzed the chemical components within a large sampling of recycled LDPE coming from separate waste collection, identifying 60 types of chemical substances that generate odors. The sampling analyzed came from the traditional mechanical recycling cycle in which the material is selected, shredded and washed with a stay in water of approximately 15 minutes. The most common odors perceived by the human nose in this sampling were: • Mold • Urine • Cheese • Earth • Fecal • Soap • Coffee • Sweaty • Pepper These families of perceived odors are created by approximately 60 chemical compounds that come together during the collection and processing phase of recycled plastic. Some critical points have been identified: The separate waste collection bag containing domestic plastic packaging to be selected in which we find different types of polymers may contain residues of substances such as detergents, food, oils, disinfectants, chemical products, creams and many others. This mixture of different chemical elements can bind to the surface of the plastic but, depending on the association time, it could also penetrate inside it. The selection between the various plastics , through optical reader machines, creates a certain percentage of error which translates into the possibility of having mixed quantities of plastics within the selected fraction. The washing phase of the ground plastic has the function of further dividing, by density, the plastics introduced and has the aim of cleaning them from the residues of products that the packaging has contained or has come into contact with. With the exception of PET, the other polymers coming from separate waste collection are generally washed in cold water, a process that does not significantly affect the cleaning process in order to reduce odors. The extrusion phase of the washed material, for the formation of the granule, could lead to a degradation of the raw material in which there are fractions of polymers other than the main one which will therefore melt at different temperatures. This can cause the formation of chemical elements that will give rise to odors. Intervening on these phases would lead to a significant improvement in the quality of the post-consumer polymers produced, not only through a reduction in the types and intensity of odors, but would also improve their technical performance. The analytical control of odors , through tools that detect their chemical origins, can help not only in the certification phase of the odorous level of the final raw material in an unequivocal and no longer empirical way, but would also provide important support in the recipe creation phase on the types of raw materials to be used during the recycling phases of plastic waste, on the identification of the best sources and on the results of the production processes in the plant (selection, washing and extrusion). Reducing odors and improving the quality of post-consumer granules would lead to the opening of new markets in which recycled raw materials could be used instead of virgin ones with an environmental, economic and industrial advantage. Category: news - technical - plastic - recycling - LDPE - post-consumer - odors See more information on LDPE recycling
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How to Identify Limonene in Post Consumer PlasticsThe presence of the smell of limonene in post-consumer plastic waste limits its use and quality With the increase in the use of post-consumer plastics in the production of articles, the problem of identifying odors in the waste to be processed has also increased and, consequently, in the granules produced following recycling. If until a few years ago the pungent and persistent odor in products made with post-consumer polymers was relatively tolerated, as they were intended for objects with limited destinations today, the massive use of these polymers in substitution of virgin raw material or post industrial waste, raises the problem of the smell of the finished product. As we have already described in several articles on the blog, on the difficulty of using post-consumer recycled plastic polymers, in the presence of annoying odors, we can deepen the subject by talking about how it is possible to control the plastic supply chain to understand both the presence and the intensity of the chemical compounds that give rise to unpleasant odors. The analysis can be done both from the point of view of the customer who buys the post-consumer polymer to produce the objects he will sell, and from that of the recycler who will have to analyze which batches of waste and in what quantities contain the substances that give rise to odors. First of all we can say that in post-consumer plastic waste there are more than one chemical substance that gives rise to a series of odors, but that some are more pungent and annoying than others. In particular, limonene is widely present and is difficult to eliminate, despite the plastic waste being duly treated with correct washing systems and adequate recycling procedures. In fact, during the reception phase of the waste packages, which have come into contact during their waste life with many other products, as well as food products, it is important to have the ability to test the incoming flows to understand the incidence of substances that will create odor at the end of the recycling process, in order to be able to manage them with careful mixing of waste that has a low level of these odorous substances. These compounds can be made on the basis of analytical data, not by sensation, so as to create a flow of raw material that can guarantee the user a certainty the percentage of odor contained in the granule. As for companies that use post-consumer plastic polymer, it is essential to establish the acceptable odor target, with analytical calculations, in order to guarantee their end customers to buy a product, made with post-consumer recycled plastics, with an odor rate according to established parameters, not empirically through the use of testers who make their nose available. This guarantee path, downstream and upstream of the process, can be carried out using a laboratory machine that uses ion mobility gas chromatography, which allows for analysis rapid (15 minutes) and automatic samples of waste or plastic granules or on finished products. A simple insertion of the sample into the tubes and into the machine, allows a detailed analysis of the presence of chemical compounds in the sample. Based on the graphic picture that the machine returns, the presence and intensity of the odorous components can be identified with certainty, taking the necessary actions to modify or accept or reject the product. 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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Recycled Plastics: How to Use Ion Mobility Gas ChromatographyRecycled Plastics: How to Use Ion Mobility Gas ChromatographyAs we have extensively described in other articles, whose links you will find in the final part of this article, the world of recycled or recycled plastics, especially those that come from separate collection, defined by post-consumption, they have the problem of managing the odorous component that is established inside the recycled raw material. Odors that come from the heterogeneous composition of the plastic in the collection phase, from the fermentation processes of the organic residues incorporated in the plastics to be recycled, from the washing water not managed in correct manner, from the degradation, during the extrusion phase of the granules, of plastics mixed with the main ones and of chemical substances absorbed by the containers during their packaging function, such as surfactants for example. The production of recycled granules made without the chemical control of the incoming material, water control and extruded materials for sale, is like driving in the night with headlights off. The commitment of company resources to purchase the raw material to be recycled, processing costs, logistics and sales costs, could be put at risk by '' impossibility of producing a raw material in recycled plastic that meets the expectations of the final customer in terms of odors. The analytical control of odors in the input materials allows us to select suppliers, divide them by categories and draw up production recipes that take into account the odor footprint of the products inbound. The same analytical control will be used to check the correct production process and formulation of recipes, not only from a technical aesthetic point of view, but also from an odoriferous one, to giving the final customer an extra quality that is increasingly sought after by the market. And, finally, the commercial can calmly propose a granule that has a license for the smell, not questionable or questionable through other noses, especially from those who are employees in the purchase of the granule produced, but through a certainty provided by a chemical analysis of the odorous components present in the product.How does this laboratory technology work? The technology underlying the instrumentation we are talking about is the GC IMS (Gas Chromatography with ionic mobility). This technology applies to volatile organic substances originating from a static headspace generated under standardized conditions. A chromatographic gas column allows the preliminary fractionation of the volatile substances introduced before entering the heart of the instrument. The heart of the instrument is made up of a 9.8 cm metal tube inside which an electric field of 5,000 Volts is created; the volatile substances from the chromatographic column are ionized by a source containing tritium (a low intensity radioactive substance). The ionization process takes place at ambient pressure and is based on the interaction between the water present in traces in the nitrogen gas which acts as a "carrier": The chemical-physical process of ionization is such that volatile organic substances such as alcohols, aldehydes, ketones, carboxylic acids, aromatic compounds, amines, thiols, halogenated compounds , etc, are electrically charged and therefore made detectable by the Faraday plate placed at the end of the flight tube. The aforementioned substances are those responsible for the "odors" that are perceived by the human sense of smell: the "extreme sensitivity" of the detection system that reaches the level parts per billion (ppb). The electronic nose is therefore made up of a GC IMS detector, coupled with an autosampler that has the task of heating the 20 ml glass bottles in which they are located the substances (liquid or solid) that develop the volatile substances. The way to perform the analyzes is extremely simple, since there is no preparation of the product to be analyzed. In the sector of recycled or recycled plastics it is really easy to prepare the samples and get the tests. The analytical result consists of a three-dimensional diagram like a geographical map of the mountains: the "geographical map" indicates the elution time from the chromatographic column, the flight time and signal strength of each individual volatile organic substance. This instrumentation therefore allows you to compare in an "objective" way the recycled plastics that emit volatile organic substances perceptible to the smell. Useful Links: POST-CONSUMER RECYCLED PLASTIC GRANULE WITH ODOR CERTIFICATION ANALYTICAL ODOR CONTROL IN THE RECYCLING SECTOR ODORS IN RECYCLED POLYMERS: HOW TO COPE WITH THE PROBLEM? ODORS IN PLASTIC: CHECK THE SUPPLY CHAIN TO AVOID COMPLAINTSABOUT THE MACHINE Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Odors in Plastic: Check the Supply Chain to Avoid ComplaintsOdors in Plastic: Check the Supply Chain to Avoid ComplaintsIf it is known that in the waste coming from separate collection and therefore from post-consumption, the presence of odors can consistently persist, once transformed into granules, the expectations on the production of raw material from post industrial waste or from post industrial + post consumer compounds, from the point of view of odors, are definitely higher. So high, that you expects not to have to face the problem of delivering to the customer plastic granules suitable for producing items that until a few years ago were made with virgin raw material, which contain an unpleasant odor gradient. The qualitative ambitions of these customers who buy the recycled plastic raw material remain high (as if they were still buying a virgin raw material), so as to be able to boast of green productions , but at the same time not having to risk losing their final customers due to an issue linked to unpleasant odors. A couple of requests that are really difficult to sustain, where the producer of recycled plastic raw material must find certain solutions to control its production chain, with the aim of avoiding to purchase scrap and manage processes that could increase the problem. But what tools do we have today to be able to create a control strategy that warns us when an incoming plastic waste can cause odors in the final granule, with the consequent possible dispute of the customer who buys it, or what tools do we have to understand if the extrusion of the raw material creates degradation processes that could generate odors? First we can say that the tool for odor control in all stages of production exists, it gives us a chemical photograph of our processes and shows us where there may be the error that will cause the dispute. This laboratory machine, the size of a desktop printer, is a gas chromatograph combined with an ion mobility spectrometer which, through a quick analysis and without preparation of the particular samples, it tells us what is, chemically, the origin of the fragrances that the human nose intercepts but which does not know how to separate them and understand their origin. If you think it will only be useful to give a scent license to the plastic granule you produce, you are only one third of the way, as the help that this type analysis can give the company not only the final control of the raw material, but also identify the critical stages of production in order to prevent odors from forming. The areas of use of the technology can be summarized here: Purchase of plastic waste for production Whether they are post consumer or post industrial, a company that produces recycled granules has several suppliers of plastic waste and, not all of them work in the same way: washing with different efficacy, waste selection with different systems and methods, risks of contamination of waste with other plastics and many other similar situations. So it is necessary to build a qualitative database of suppliers, as regards the odors of waste, so that you can, chemically, have a photograph of what it is waste it can contain and how this waste could behave in its transformation into plastic granule. The chemical analysis of the incoming flows makes us understand which supplier, by raw material, we can use to create our granule recipes, without generating unpleasant odor problems in the production phase. The flow analyzes create a database through which you can attribute a specific waste of a particular supplier to a specific recipe. If the chemical photograph of a flow of plastic waste contemplates the presence of a series of chemical compounds in a certain quantity, we can know with certainty which odorous imprint the our final granule. Granulation of plastic wasteIn this phase it may happen that, without a chemical photograph of the input entering the extruder, the waste can be used for the production of granules, without we can intercept a particular odor disturbance, thus trusting to produce a good quality granule, perhaps comforted by the fact that the laboratory analyzes that are normally done, such as density, DSC, ashes and fluidity, tell us that the material can be eligible. But during production there may be very small fractions, in terms of quantity, of materials unrelated to the main raw material, which can degrade creating important odor signals that could have the material contested. The chemical photograph gives us indications that are expressed in values so small that the chemical compounds entering the extruder and those that can be generated during processing, are precisely intercepted and analytically defined. So even the control of the extrusion phase of recycled plastics gives us a precise, non-empirical picture of odors, on which we can work for a possible adjustment of the recipes . Quality control in sales and after salesHow can you define a smell of a recycled polymer? Seen by the manufacturer in one way, seen by a buyer perhaps in another. This difference in evaluation creates the greatest number of disputes and commercial embarrassments which, at times, ends with a surrender of the producer for lack of certain proof. This yield almost always turns into economic damage to be recognized to the customer by the polymer manufacturer but, in most of the times, there is also a commercial uncertainty between customer and supplier managed in a completely empirical way through the nose test. The customer has his men who smell the smell of the granule they receive and give an evaluation, while the supplier provides his team. In both cases, the human nose, however sophisticated, can interpret the smell in a different way. To resolve the uncertainty, possible disputes and possible loss of trust on the part of the customer, providing them with a chemical photograph of what you are selling is the best way to demonstrate that the product is made up of chemical elements that can generate odor gradients within the limits that the customer has previously accepted, not through a questionable nose but through chemistry. In fact, customer and supplier can create, in a certain and analytical way, an agreement that limits certain chemical substances that generate odors to values accepted by both parties. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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HDPE: Production of Bottles with Recycled Plastic | Some AdvicesHow to solve aesthetic problems in the production of recycled HDPE bottles The demand for regenerated HDPE for blow molding has seen a strong surge in recent years, certainly finding some producers not totally prepared to manage the recycled granules in their machines. It was not just a question of the type of granule which may differ slightly, from a technical point of view, from the virgin raw materials in their behavior in the machine, but problems related to the tone of the colors, stress cracking and the tightness of the welds had to be addressed , micro holes and other minor issues. In previous articles we have addressed the genesis of recycled HDPE in bottle blowing and the correct choice of recycled raw materials, while today we see some aesthetic aspects that could arise using 100% recycled HDPE granules. There are four aspects, from an aesthetic point of view, which can negatively impact the good production result: 1) A marked porosity called "orange peel" which forms mainly inside the bottle but, not rarely, is also visible on the outside. It appears as an irregular surface, with the presence of continuous micro cavities which give a wrinkled appearance to the surface. Normally the problems are to be found in the granule, where a possible excessive presence of surface humidity does not allow perfect laying of the HDPE wall coming out of the mould. In this case the problem can be solved by drying the material in a silo so that it reaches a level of humidity that will not negatively affect the surfaces. Generally speaking, it is always a recommended operation when you want to produce using 100% regenerated material. 2) Streaks on the bottle are another aesthetic problem that occurs for different reasons, especially if you use an already colored granule. The causes may depend on a different percentage of plastic inside the HDPE granule, even in minimal percentages, between 2 and 4%, since, since the plastics have different melting points, the aesthetic behavior on the wall of the bottle can be slightly different, affecting the color in the dough. It is important to note that the streaks of tone should not be confused with the streaks of structure, which are normally created by the bottle mold due to wear or dirt that accumulates while working. Another reason may depend on the heat resistance of the master used, as it is not uncommon that at temperatures that are too high, both during extrusion of the granule and blowing of the element, a color degradation phenomenon can be created with the creation of small streaks on the walls of the bottle. 3) Perfect weldability in a bottle is extremely important as any detachment of the walls, once the bottle has cooled and filled, causes serious damage with costs to be incurred for the loss of the packaging, the substances contained and the replacement of the material with significant logistics costs. The newly produced bottle normally does not present the possible defect as the temperature at the exit from the machine "hides" the problem a bit, but once the bottle has cooled down, filled and subjected it to the weight of the pallets that are stacked on top it, a welding defect can present itself in all its problems. The cause of this problem must normally be sought in the percentage of polypropylene that the HDPE granule may contain due to a non-optimal selection of raw materials upstream of the production of the granule. A poor selection of the bottles among themselves, but above all from the caps they contain, can increase the percentage share of polypropylene in the granule mixture. There are machines on the market with optical selection of the washed ground coffee that help to substantially reduce this percentage, bringing it back below 1.5-2%. When purchasing a load of recycled HDPE it is always a good idea to ask for a DSC test to check the composition of the granule for production. The effect of an excessive percentage of PP has as a direct consequence the prevention of effective welding of the contact surfaces that form the bottle. In addition to working on the granule, it would be a good idea, if you wish to use 100% recycled raw material, to slightly increase the overlap thickness of the two sides of the bottle to favor the correct welding point. 4) The presence of micro or macro holes in a bottle , visible directly through an inspection or, for smaller ones, through the air tightness test, may depend on the presence of impurities inside the granule, when washing and the filtering of the raw material was not done to perfection. Another reason may depend on poor cleaning of the screw of the blowing machine which can accumulate residues of degraded polymer and subsequently transport them outside towards the mould. Especially if you use recipes with mineral filler, the problem may arise immediately after changing the recipe from one without filler to one that contains it. Category: news - technical - plastic - recycling - HDPE - post-consumer - bottles
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The Use of Mineral Fillers in the Production of Recycled HDPE BottlesAdvantages and disadvantages in blowing bottles with recycled HDPE granules loaded with Talc or Calcium Carbonate The production of single-layer HDPE bottles has always been competence of virgin polymer until a few years ago, with which colors, thicknesses, finishes, fragrances and shapes were made without worrying too much about the polymer-blow molding ratio. The advent of recycled HDPE in the blow molding world has been gradual and quite complicated, as there was a certain mistrust on the use of rHDPE, motivated by hypothetical doubts on mechanical strength, on the quality of the surfaces, on the seal of the handle, on the smell of the blown packaging, on the realization of the colors and the transparency to see the liquids inside, on the sealing of the welds, on the micro perforations of the surfaces, on the availability of the material and on the small difference in price compared to virgin raw material. All legitimate objections for those used to using virgin polymer, but many of them were general preconceptions about recycled material, which was still seen as synonymous with lower quality general. There is no doubt that the first years in which HDPE recycled in blow molding granules arrived on the market, the quality of the recycling and sorting plants attributed to the raw material some objective limits. The main critical issues were related to some technical factors: • Impurities contained in the granule • Excessive presence of PP • Presence of residual moisture • Persistent odor • Hardly manageable color We do not go into how the recycling sector has technically, over the years, solved the problems exposed, managing to create a recycled HDPE granule that is comparable, from point of overall performance, many times to the virgin one. Perhaps, in some cases and with some machines, the question of the thickness of the bottle is still an open topic, as, at times, it may be necessary to increase in thickness using rHDPE compared to the first choice. The reason why it may sometimes be necessary depends on many factors, such as the shape and size of the bottle, the blow molding machine you use, the quality of the recycled granule, all elements necessary to achieve a correct ratio, between the compressive strength of the bottle and the weight that weighs on it once inserted into a vertical pallet. It is possible to overcome this inconvenience, after verifying and solving the previous problems, through the use of mineral fillers such as talc or calcium carbonate. The function of mineral fillers is to increase the vertical compressive strength of the bottle, without having to increase its thickness, through the use of percentages that do not exceed usually 10-15%, depending on the size of the product to be made. It should be noted, by engaging loaded granules, that the bottle enjoys advantages relating to load resistance and torsion, thus improving portability and economy in the production phase . There are, however, some information to keep in mind when deciding to operate by blowing with an rHDPE granule loaded with talc or caco3: • The screws of the blow molding machine must be cleaned often, as the first stages of using an abrasive mixture, such as loaded HDPE, facilitates the transport of contamination present in the blowing machine with the possibility of creating holes in the bottle. • The presence of mineral fillers can affect the transparency, or semi transparency, of the product. • The creation of colors must take into account a possible different color result compared to a rHDPE without fillers. • The presence of PP, even in low percentages, in a loaded granule, further reduces the sealing and sealing capacity of the bottle, especially in the handles or in points with particular angles. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Analytical Odor Control in the Recycling SectorAnalytical Odor Control in the Recycling SectorRecycled materials, which are raw materials from the selection of waste, in their various states of life (loose, bales, ground, granules), o the final product, created through recycling processes, can bring with them gradients and types of odors that can be more or less unpleasant to operators or end customers. The sensation of acceptance or not of smell is entirely subjective and depends on an infinite series of sensory evaluations: what for me could be an acceptable smell, for the customer could be an unbearable home. The human nose is sensitive, but different between person and person in intercepting odors and, above all, it is not able to accurately catalog an equal level of odorous compounds, nor the repetition of the intensity of the odors it intercepts. What a company produces, in terms of smell on a product , whether it is raw material or a finished element, must be cataloged in a completely analytical way, without approximation, to determine standards that can accepted by both the producer and the customer, so that all subsequent productions can fall within the established ranges. Defining and being able to replicate a range of odors accepted by the parties is not only an increase in the qualitative service of the product itself and of the company, but also a guarantee towards the end customer who can reasonably know that the odor intensity can be cataloged and managed exactly. Let's see some examples where an "electronic nose" can make the difference: • Producers of PET trays, receiving the recycled granule or ground, can analytically evaluate the odor intensity of the raw material and give the producer himself standards not to be exceeded to avoid problems on the trays in the distribution chain. • Manufacturers of beverages in PET bottles can establish with certainty not only the maximum odor levels accepted on the raw material, but they can establish whether the product contained in the bottles can undergo transfers by the plastic bottle of odorous substances that can affect the quality of their product. • Producers of raw materials can establish with their customers the maximum odor ranges acceptable to both, through an analytical analysis of the material first sold in order to ensure a reliable product quality. • The manufacturers of bottles for detergents , for care, for perfumed liquids need to purchase recycled raw material in HDPE that has an odor content coming from the surfactants such that they do not interact negatively with the final packaging on the shelves of the shops or can alter the fragrance of the liquids or powders contained. • Furniture or packaging manufacturers for industrial logistics who use PP, HDPE and LDPE from post consumption, they must be able to establish with certainty the incidence of the odors of the raw materials they buy, in order to establish limits that cannot negatively affect the final product they distribute. • We could continue to cite other examples in which the lack of a certain classification of odors can often lead to the dispute of the materials, with considerable costs and degeneration of customer-supplier relationships. Through the use of an odorous substance analyzer , a laboratory machine that uses samples of raw materials or pieces of final products , therefore in the form of granules, ground, liquids, etc ..., which are heated, creating volatile substances inside the test tube, which are then chemically analyzed and compared, through an analysis program, this creates a precise picture of the types and intensities. The machine allows you to compare also standard samples and therefore accepted by the parties, with the various production samples in order to intercept the deviations and immediately evaluate production corrections. The results of the analyzes return a precise photograph, not only of the odor intensity, but also of the types of chemical compounds present in the samples that produce the mix of odors, so as to be able to intervene in a precise and timely manner. The tool that analytically analyzes the smells or fragrances of the volatile substances contained in the products is also used in the food sector to unmask food sophistications such as, for example, those of olive oil, to verify the compositions of coffee, to evaluate the freshness of food or the transfer of substances contained in the packaging to food. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Nano Polymeric Coatings with Antimicrobial Properties. Where are We?Polymers containing nanoparticles with the ability to inhibit the proliferation of many microorganisms, in the packaging, transport and hospital sectors. The microorganisms that surround us and that can cause discomfort, disease and even death in some cases, they are invisible to the eye of man but, not only do they keep us company in every place we are, but often we ourselves carry them from one place to another, during our daily life. Scientific research has been studying the phenomenon for years, it is not so much focused on direct intervention to disinfect the surfaces we touch, but rather on avoiding the proliferation mechanism of microorganisms on the surfaces. By surfaces we mean all those objects that, directly or indirectly, can be vectors of contact with our body and, consequently, could cause diseases of rapid diffusion. This is true for the world of packaging, for hospitals, for means of transport, in our homes, for places of social gathering, in short, in all those situations in which microorganisms have an easy time to replicate. From a technical point of view, this phenomenon can be understood in what is called biofouling, that is, biological contamination processes deposited on the surface of materials. This process begins with the formation of a primary film on the surface of the material in the presence of at least two variables, microorganisms and moisture. Among the predominant microorganisms are bacteria and diatoms, which produce a large amount of organic matter, such as polysaccharide acids that form a surface film with many nutrients, which is used for the colonization of other larger organisms. For example, in the health field, it has been discovered that micro-films, composed of microorganisms, can form in medical devices such as vascular catheters, joint prostheses and catheters urinary, which was, at times, resistant to antibiotics. Other areas under observation are for example means of transport or hospitals, whose fight against infectious microorganisms is fought with metal nanoparticles available in many types and quantity. In this way, the nanoparticles Cu, ZnO, Se, ZrO 2, SiO, TiO 2, among others, can be used in all social places and our homes in the presence of high humidity. The carrier for the nanoparticles can be a polymer, of any type, which constitutes the products, for example, silver or copper nanoparticles, are materials interesting that can be used to combat biofouling, as they have broad spectrum antimicrobial properties and are effective against multiple bacteria, viruses and fungi. Furthermore, iron oxide nanoparticles also have antimicrobial characteristics, but their study was less extensive than Ag and Cu nanoparticles, but it is important to note that their biocompatibility is an important reason to implement their use in commercial products such as those for packaging. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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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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If the food is consumable, the new bio film tells youThe new packaging changes color based on the quality of the food it contains University and scientific research in the field of packaging is focusing on the problem of the effective expiration of food, studying bio films that can help us classify, in addition to the label affixed, the real quality of the food contained. The new bio-films are made of bio-plastics, made from the transformation of sugar contained in beets and corn, to which additives are added from waste from the agri-food sector. These additives are, in turn, waste from the agri-food chain such as hemp, flax, coffee waste, various vegetation waste, and other natural products . They have several properties that we can summarize: · Good mechanical properties · Fire resistant · Antioxidant properties · Antifungal properties · Antimicrobial properties Among the additives we talked about earlier, the addition of zinc oxide and aluminum, in the production of bio films, develops antimicrobial properties that can lengthen the expiration of fresh products, thus reducing the waste given by the expiration of the products. While the addition of an additive such as cardarol oil and a particular molecule called porphyrin, they attribute to the film antioxidant and antifungal properties , which in the field of food packaging help to signal the deterioration of the product. But how does this mechanism happen? When the bio film comes into contact with some analytes, such as water, ethanol, ammonia or other products that derive from food degradation, in combination with light, these toxic elements penetrate the polymer of the film creating color reactions . The films made in the laboratory are completely biodegradable and bio compostable , this means that at the end of their life cycle they can become fertilizer and re-enter in full respect of the circularity of the products.Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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RFID Labels, NFC Tags, and Compostable Freshness Indicators: Frontiers and Sustainable Innovation for Food and Pharmaceutical PackagingTowards intelligent and fully compostable packaging: challenges, solutions and perspectives for the integration of sustainable electronic devices into organic waste collection flows by Marco Arezio In recent decades, the packaging industry has undergone a veritable revolution . While packaging was once simply a means of containing, protecting, and transporting goods, today it has become a vehicle for information, security, interaction, and, increasingly, environmental sustainability. The advent of the Internet of Packaging (IoP) has enabled the packaging of food, pharmaceutical, and consumer goods to be enhanced with smart labels: RFID, NFC tags, and freshness indicators are now well-established features on the production lines of global companies, offering new levels of traceability, authenticity, and quality control. However, this push toward digital innovation is accompanied by an even more pressing challenge: managing the end-of-life of packaging containing electronic components without increasing environmental impact, integrating these devices into the virtuous cycle of the circular economy. Thus, smart packaging today finds itself at a crossroads: become truly sustainable, or risk becoming a new disposal problem. Smart Packaging and New Traceability and Safety Needs The spread of smart packaging arose from the need for ever-increasing information on a product's life cycle: where it comes from, how it's stored, and whether it's been handled correctly throughout the supply chain. RFID labels and NFC tags allow for unique product tracking, facilitating both logistics and inventory management, while freshness indicators and environmental sensors can detect any changes in temperature, gas, or humidity in real time, flagging alterations that could compromise the safety or quality of the food or drug. These technologies are now essential for companies seeking to reduce waste, ensure consumer safety, and meet market demands for transparency. However, the very presence of electronic components, if not properly designed, can compromise the packaging's ability to be recycled or composted, contaminating organic waste streams and posing a potential environmental risk. Environmental issues of traditional electronic devices The enthusiasm for smart packaging still faces limitations imposed by the use of conventional materials in the manufacture of electronic labels. These devices are typically constructed using plastic substrates such as PET or PP, conductive tracks made of copper, silver, or aluminum, silicon microchips, and synthetic adhesives. None of these materials can be considered truly biodegradable or compostable; in fact, they often release microplastics and heavy metals. If dispersed in organic waste streams, they can degrade the quality of the compost produced, posing a risk of contamination for soil and crops. For this reason, European (EN 13432) and American (ASTM D6400) regulations are imposing increasingly stringent criteria not only for packaging materials , but also for all functional components, including electronics, requiring complete compostability for everything accompanying the product at the end of its life cycle. The architecture of a compostable smart label: innovative materials and production processes Scientific and technological research has responded to these new environmental challenges with unprecedented effort, leading to the development of a new generation of labels and sensors that are designed from the ground up to be compostable. The foundation of these solutions lies in bio-based substrates, i.e., supports made from renewable raw materials such as PLA (a polymer obtained from the fermentation of plant sugars), regenerated cellulose, or PHB, a microbial biopolymer . These materials are not only compatible with modern electronic printing techniques, but also degrade safely both in industrial composting facilities and, in some cases, even in domestic environments. The second revolution concerns the materials used for conductive tracks and circuits: instead of traditional heavy metals, carbon-based inks, graphite, or carbon nanotubes, and organic conductive polymers such as PEDOT:PSS or polyaniline, all capable of degrading during composting, are gaining ground. "Green" versions of metal conductors—such as encapsulated silver nanoparticles—are also finding application, albeit with some limitations in terms of cost and durability. The real quantum leap, however, is in eco-friendly microchips and sensors : today, work is underway on organic transistors on cellulose substrates, fully biodegradable thin-film devices, and transient memories that dissolve upon contact with moisture. Although their performance is limited compared to traditional silicon chips, these solutions are already sufficient for short-cycle NFC and RFID tags, ideal for timely monitoring and disposable packaging. Finally, freshness indicators can be made without electronics , using reactive films based on natural substances such as pectin, alginates or plant pigments, capable of changing colour depending on the presence of gas or temperature variations: safety information immediately usable by the consumer and, above all, completely biodegradable. Industrial production and integration techniques Innovations in materials have also driven rapid evolution in manufacturing processes. Compostable smart labels are now produced through inkjet printing with conductive inks on bio-based substrates or paper, screen printing to create thicker and more robust circuits, and low-temperature lamination or bonding to avoid altering the properties of compostable materials. Great attention is also paid to adhesives, favoring natural starch- or dextrin-based ones to avoid any risk of contamination in organic flows. The goal is to integrate these technologies into existing production lines, ensuring scalability, efficiency, and cost competitiveness. Current limitations and technical challenges Although the results are promising, the road to full adoption of compostable labels is not without obstacles. The first limitation concerns durability: these devices are ideal for products with a short shelf life—such as fresh food or single-dose pharmaceuticals—but less suitable for long-term logistics. The communication range of passive RFID or NFC tags, for example, is still lower than that of traditional metal circuits, especially at higher frequencies. On the economic front, production costs, though declining, remain higher than conventional solutions, although growing demand and industrialization are rapidly closing the gap. Finally, there are some compatibility issues with standard reading systems, often optimized for metal labels, which will require technological updates and adaptations by logistics and industrial operators. Real-world applications and case studies Despite these limitations, numerous success stories demonstrate that the compostable smart label revolution is already a reality. In the food sector, for example, some companies are experimenting with packaging for ready-to-eat salads, meat, and dairy products equipped with freshness indicators and compostable NFC tags, capable of monitoring the cold chain and ensuring quality all the way to the end consumer. In the pharmaceutical sector, too, blister packs and "smart" packaging are being equipped with compostable NFC tags, offering secure traceability and facilitating sustainable disposal. In logistics and e-commerce, compostable bags and boxes with integrated smart tags enable product authentication and tracking throughout the supply chain, without increasing the residual waste fraction. Regulations and standards: a race towards compliance Regulatory compliance represents a crucial step for the widespread use of smart and compostable packaging. The EN 13432 and ASTM D6400 standards are now the benchmark for certifying the compostability of materials, establishing precise limits on biodegradability, disintegration, the absence of heavy metals, and ecotoxicological safety. Certification bodies are updating their protocols to include electronic devices, paying particular attention to food safety and the environmental impact of the compost produced. The direction is clear: only devices that comply with these requirements can be fully integrated into organic waste collection flows. Research perspectives and future scenarios Research continues unabated; in fact, it accelerates on multiple fronts. The move toward transient and disassembled electronics , devices designed to dissolve spontaneously or be easily separated from compostable materials, is gaining traction. On-demand circuit printing on biodegradable materials is becoming increasingly popular, useful for customizing information throughout the supply chain. Solutions are being explored that integrate traceability with blockchain and IoT without compromising environmental compatibility. Finally, great attention is being paid to consumer education: clear instructions and intuitive symbols are essential for proper disposal and to avoid the risk of contaminating organic waste streams. This revolution is supported by a strong collaboration between academia, industry, and regulators, with the aim of standardizing new technologies and accelerating the transition to smarter, more sustainable, and environmentally friendly packaging. Conclusions: the future of smart packaging is compostable Never before has packaging innovation faced such a crucial choice: continue to grow by focusing on intelligence, traceability, and interactivity, or stop to avoid increasing environmental pressure. The integration of RFID labels, NFC tags, and compostable freshness indicators represents the synthesis of these needs, demonstrating that it is possible to combine advanced technology and respect for the environment. Advances in materials, production processes, and regulations have paved the way for truly smart packaging that is simultaneously fully compatible with organic waste collection and the principles of the circular economy. Technical and economic challenges remain, but the industry's direction is clear: the packaging of the future will be increasingly integrated, interactive, and sustainable. The challenge now lies in the speed of this transition and the ability to work collaboratively between research, industry, and policymakers to build an innovative, transparent, and truly green supply chain, without compromising the health of the planet. © Reproduction Prohibited
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The Role of Calcium Carbonate in the Production of Raffia and PP Raffia FabricsA Technical Insight into the Use of CaCO₃ as a Functional and Sustainable Additive for the Polypropylene Textile Industryby Marco ArezioThe use of calcium carbonate (CaCO₃) in plastics—and particularly in the production of raffia and PP raffia fabrics—is among the most established and strategic practices in the modern polymer industry. Although it was initially introduced merely as a filler to reduce production costs, CaCO₃ has evolved into a multifunctional additive capable of deeply modifying the physical-mechanical, optical, and thermal properties of polypropylene, while also enhancing the overall sustainability of industrial processes.In raffia fabrics—used in applications ranging from packaging sacks to geotextiles—calcium carbonate is no longer considered a simple additive, but rather a key component for structural and production optimization.The Industrial Context of PP Raffia FabricsIn technical terminology, the word raffia refers to extruded polypropylene tapes (tape yarns) which, after being stretched, acquire a strong and lightweight structure similar to natural fibers. These filaments are then woven or knitted to obtain versatile materials: from classic industrial bags for cereals, seeds, polymers, and cement, to agricultural sheets, drainage geotextiles, and technical furnishing components.However, polypropylene exhibits several limitations familiar to materials technologists: it is a semicrystalline polymer, prone to shrinkage, somewhat brittle at low temperatures, and often difficult to stabilize dimensionally during extrusion. Within this context, calcium carbonate plays an essential technical role.Properties and Behavior of Calcium CarbonateCaCO₃ is an abundant, stable, thermally inert mineral that is compatible with many polymeric matrices. From a morphological standpoint, its particles—either natural or precipitated—offer a contact surface that interacts with the polymer during compounding and extrusion. This interaction is not chemical but physical-mechanical: the particles act as nucleating agents for PP crystallization, promoting faster cooling and a more controlled crystalline orientation.The result is a more homogeneous structure, improved shrinkage control, and greater process stability—factors that are crucial when operating continuous, high-speed extrusion lines.Improving Processability and Dimensional StabilityDuring the extrusion of polypropylene film destined for raffia, CaCO₃ acts as a nucleating agent that accelerates crystallite formation, improving solidification and the subsequent slitting of the film into tapes.The presence of the mineral reduces thermal deformation, ensures more uniform thicknesses, and stabilizes draw ratios during stretching. In modern industrial processes, where quality consistency is critical, even slight variations in melt flow can compromise weaving performance; the inclusion of CaCO₃ mitigates these risks by stabilizing the rheological behavior of the polymer melt.Enhancement of Mechanical and Surface PropertiesMechanically, the effect of CaCO₃ on PP raffia is twofold: it increases rigidity and improves abrasion resistance. This is particularly important for products subjected to repeated friction, such as industrial or construction sacks, big-bags, and technical sheets.Moreover, mineral particles provide higher opacity and improve surface finish, enhancing printability while reducing the excessive gloss typical of pure PP. The resulting aesthetic effect is more textile-like—matte and natural—an appreciated feature in high-quality packaging applications.Types of Calcium Carbonate: GCC and PCCThe distinction between GCC (Ground Calcium Carbonate) and PCC (Precipitated Calcium Carbonate) is crucial from an industrial standpoint.GCC, produced through mechanical grinding of limestone, offers a lower cost and a broader particle size distribution suitable for standard applications.PCC, on the other hand, is obtained by controlled precipitation, resulting in finer, more spherical, and uniform particles. This morphology enhances dispersion within the polymer, yielding smoother surfaces, greater opacity, and improved tensile performance.The choice between the two depends on economic factors, target applications, and compatibility with other additives or color masterbatches.Thermal, Rheological, and Optical AspectsOne of the most relevant effects of CaCO₃ addition is the increased thermal conductivity of the compound, which enables faster cooling of the extruded tapes, shortening cycle times and boosting productivity.From a rheological perspective, the viscosity of the filled polymer becomes more stable and predictable, facilitating control over extrusion temperatures and pressures.Optically, calcium carbonate enhances opacity and ensures more uniform coloration, improving print quality in flexographic and screen-printing processes—essential features for product branding and traceability in industrial packaging.Economic Benefits and Environmental ImpactThe inclusion of CaCO₃ reduces the amount of virgin polypropylene required per unit of product, offering substantial cost savings. Yet the benefit is not purely economic: since calcium carbonate is a naturally occurring mineral not derived from petroleum, its incorporation contributes to lowering the overall carbon footprint of the final product.Furthermore, modern compounding systems allow for CaCO₃ derived from mining by-products or recycled marble residues, embedding raffia production within a broader circular economy framework.The resulting fabric remains compatible with conventional mechanical recycling processes for PP, as the filler does not significantly alter thermal behavior nor release harmful substances during reprocessing.Research and Innovation Perspectives in PP–CaCO₃ CompositesRecent studies in polymer composite materials have focused on surface functionalization of calcium carbonate through fatty acid or silane treatments to enhance adhesion with the polymer matrix.These surface modifications improve load transfer efficiency between mineral and polymer phases, reducing brittleness and expanding the range of possible applications.There is also a growing interest in advanced masterbatches containing ultra-fine CaCO₃ (<1 μm), which ensures superior dispersion and tangible improvements in mechanical and optical properties even at lower loadings.The technological evolution of PP raffia with mineral fillers is therefore moving toward advanced material engineering, where production efficiency, sustainability, and aesthetic quality coexist in a refined industrial balance.ConclusionsThough seemingly simple, calcium carbonate plays a complex and strategic role in polypropylene raffia. It enhances polymer processability, regulates thermal behavior, increases stiffness and opacity, reduces costs, and supports the environmental sustainability of the production chain.Its function extends beyond technical improvement, becoming integral to a production model that emphasizes energy efficiency and the valorization of secondary mineral resources.In the near future, stronger collaboration between academic research and the masterbatch industry will likely refine PP–CaCO₃ compatibilization even further, paving the way for lighter, stronger, and more recyclable technical fabrics.In this sense, the next generation of raffia will not merely be an efficient industrial product but also a symbol of sustainable innovation within the polymer textile sector.© All Rights Reserved
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Polymeric Coatings for Metal Food PackagingPolymeric Coatings for Metal Food PackagingMetal boxes for food preservation have a long history but, if in the past, they had deficiencies from the hygienic and toxicological point, especially in because of the welds that were made in Sn-Pb alloy, currently the quality of the manufactured products are much better. Today the protection of food is mainly entrusted to the polymeric layer of inner coating , called coating , which stands between the metal wall and the contained food. The primary function of this barrier is to protect food products from light, oxygen, enzymes, humidity, pollutants and microorganisms that would result in the modification of the structure of the food and its quality. The aim is also to increase the useful life of the food or the drink which in normal, that is, not canned, it would deteriorate more quickly, as the biochemical and enzymatic reactions and the activity of microorganisms would normally run their course. Therefore, to increase the life of the food, the metal packages are normally coated with synthetic resin film applied to the metal sheet again flat, film with a thickness of a few microns. The choice of the type of resin depends on its mechanical, chemical or thermal characteristics based on the content they must host. Below we can list the main ones: • Rosin consists mainly of abietic acid, which is normally added with ZnO to control the chemical reactions that are formed through the sulfur amino acids of proteins. • Vinyl resins are from the family of thermoplastic resins, normally PVC, which have excellent resistance to acids, but have the defect to absorb food pigments. • Phenolic resins are composed through the polymerization of formaldehyde and phenol which have excellent resistance to heat treatments, PH and to fats. Through the formaldehyde content we can identify two families of phenolic resins: Novolacche (thermoplastic) and Resoli (thermosetting). • Epoxy Resins are thermosetting resins consisting of bisphenol A and epichlorohydrin which are the most common coating in canned foods, especially in fish-based foods in oil. • Polyester resins are thermosetting resins obtained from different monomers such as phthalic anhydride, maleic anhydride or fumaric acid, integrated with vegetable oils and pigments. They have the characteristic of flexibility giving this characteristic to the metal wall layer. • Epoxy-Phenolic Resins are the result of the polymerization of epoxy resins with phenolic ones through catalysts. They are used as a transparent coating for many metal cans that contain oil, vegetable or pet food preserves. As regards the toxicological characteristics there are specific legal regulations that place limits on the possible migration of packaging substances into food, in which both specific migration and global migration are considered. However, the scientific community has given new impetus to studies and research on the toxicological aspects relating to plastics used in the food industry, with particular attention no longer to the single element that constitutes the packaging, but takes into consideration the cocktail effect that is given by all the elements that come into contact with food translated over time and with different thermal characteristics. Undoubtedly the food or drink contained in the packaging at the time of packaging has certain characteristics, but over time and in different climatic conditions , the quality of the food that arrives on the table could be different. Therefore it would be advisable to verify it through a chemical analysis, on a sample, with an instrument composed of a gas chromatograph and a spectrometer ion mobility that, in a simple and rapid way, will give the photograph, analytical, of the quality of food or drinks. Automatic translation. We apologize for any inaccuracies. Original article in Italian.
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Recycled LDPE Bags: How to Avoid Quality ProblemsRecycled LDPE Bags: How to Avoid Quality Problems The world of recycled LDPE bags is widely represented by the type we use every day for separate waste collection which, through their different colours, help us to separate waste correctly. The trend in bag production was represented by the maximum reduction in thickness and the use of increasingly lower quality raw materials. All this was part of a market logic in which the bag had to cost less and less, thus creating products that were increasingly less performing from a qualitative point of view. The major problems encountered were the following: • Fragility of the bag under the effect of the weight of the waste introduced with breakage of the walls due to breakthrough • Detachment of the welding points of the lips of the bag with vertical opening of the same • Cutting the bag if there are impurities on the wall • Irregularity of the surface with phenomena called “partridge's eye” • Difficulty in creating colours • Pungent odor from the bags even after a long time • Dryness of the bag due to the use of collected films degraded by the sun, especially the waste coming from agricultural greenhouses All these problems should be analyzed individually as each point has a long story to tell and a clear path to its resolution. In today's article we take a leap, arriving directly at the recipes that can solve all these problems, allowing the production of qualitatively correct bags with an eye on general production costs. Most of the problems listed derive from the 100% use of post-consumer input , from separate collection or agricultural sheets, whose mechanical recycling, although excellent with the new production lines, involves many of the problems mentioned. Certainly, a higher quality of the recycling lines , understood as selection, washing, densification, filtration and extrusion of the granules, corresponds to a lower quantity and importance of problems, but the mechanical recycling of waste coming from separate waste collection or from the agricultural sector, however, has of the qualitative limits that have not yet been resolved to date. For this reason, the attention to the preparation of recipes for compounds, created with attention to the resolution of these problems, gives the possibility of creating LDPE granules, coming from recycling, with superior qualities, remaining in the perspective of the circular economy which requires the consumption of waste that we create every day. The compound should contain a significant part of an LDPE film input that does not come from separate waste collection , not necessarily of post-industrial origin, but from waste that has not been mixed and polluted by other mixed plastic materials. Based on the characteristic of the final product to be made, it will be decided how to compose the input recipe, so as to be able to guarantee the quality expected by the customer. The qualitative indices must solve the problems we have talked about by taking into account some indications: • Allow bag production starting from 20 microns • The elasticity must be greater than a recipe with 100% post-consumer • The sealing strength, even when cold and under the weight of the contents of the bag, must be high. • The absence of small foreign bodies, which are formed due to the degradation of materials other than LDPE during extrusion, which affect the accidental longitudinal cut of the product. • Being able to create a smooth surface, without small corrugations or irregularities. • The recipe must include the possibility of making films with light and dark colours, semi-transparent in smaller thicknesses. • Absence or marked reduction of the pungent odor typical of post-consumption must be possible. On the basis of correct modulation of the material input and attention to the recycling and granulation phases, it is possible to significantly improve the quality of the LDPE bags produced , with a greater contribution margin on production and greater satisfaction of the end customer, always having costs under control. Category: news - technical - plastic - recycling - LDPE - post-consumer - bags - film - quality Related articles: WHAT QUALITY OF FILM CAN BE OBTAINED BY USING RECYCLED LDPE? LDPE RECYCLED FROM POST CONSUMER: 60 TYPES OF ODORS OBSTACLE SALES LDPE FROM POST CONSUMER. HOW TO REDUCE IMPERFECTIONS. EBOOK See more information on LDPE recycling
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HDPE Recycled Bottles: How to Manage Surface DefectsHow to solve aesthetic problems in the production of recycled HDPE bottles: porosity, streaks, detachment and holesThe production of bottles for detergents , for industrial and agricultural liquids, until recently were produced with virgin materials despite some shapes and colors allowed the use of a recycled HDPE granule. The media impact of plastic pollution dispersed by humans in the environment, has moved the conscience of consumers putting pressure on states, which deal with environmental legislation, but also producers of substances contained in bottles that cannot, for commercial reasons, to lose the consent of its final customers. The demand for regenerated HDPE for blow molding has had a strong surge in the last years, surely finding, a part of the producers, not totally prepared to manage the recycled granule in their machines. It was not just a question of the type of granule that may differ slightly, from a technical point of view, from virgin raw materials to machine behavior, but problems with color shades, stress cracking and seal welding had to be addressed. , to micro holes and other minor issues. In previous articles we have addressed the genesis of recycled HDPE in bottle blowing and the correct choice of recycled raw materials, while today we see some aesthetic aspects that could occur using recycled HDPE granules at 100%. There are four aspects, from an aesthetic point of view, that can negatively affect the good production result: 1) A marked porosity called “orange peel” which is formed mainly inside the bottle but, not infrequently, is also visible on the outside. It appears as an irregular surface, with the presence of continuous micro-cavities that give a rough appearance to the surface. Normally the problems are to be found in the granule, where a possible excessive presence of surface humidity does not allow a perfect laying of the HDPE wall coming out of the mold. In this case the problem can be solved by drying the material in a silo so that it reaches such a degree of humidity that it will not negatively affect the surfaces. In general it is always a recommended operation when you want to produce using 100% regenerated material. 2) Streaks on the bottle are another aesthetic problem that occurs for different reasons, especially if an already colored granule is used. The causes may depend on a different percentage of plastic inside the HDPE granule , even in minimum percentages, between 2 and 4%, since, having the different plastic melting points , the aesthetic behavior on the wall of the bottle can be slightly different, influencing the color in the dough. It is important to note that you should not confuse the streaks of shades with the streaks of structure, which are normally created by the mold of the bottle due to wear or dirt that accumulates by working. Another reason may depend on the heat resistance of the master that is used, as it is not infrequent that at too high temperatures, both in the extrusion phase of the granule and in the blowing of the element , a phenomenon of color degradation can be created with the creation of small streaks on the walls of the bottle. 3) Perfect weldability in a bottle is extremely important as any detachment of the walls, once the bottle has cooled and filled, causes serious damage with costs to be incurred due to the loss of the packaging, the substances contained and the replacement of the material with important logistics costs. The bottle just produced normally does not present the possible defect because the exit temperature from the machine “hides” the problem a little, but once the bottle has cooled, filled and subjected to the weight of the pallets that are stacked above it, a welding defect can present itself in all its problems. The cause of this problem normally must be sought in the percentage of polypropylene that the HDPE granule can contain due to a selection of the raw materials upstream of the non-optimal granule production. A poor selection of the bottles between them, but above all from the caps that they contain, can increase the percentage of polypropylene in the granule mixture. There are commercially available machines with optical selection of the washed ground which help to substantially reduce this percentage, being able to bring it back below 1.5-2%. When buying the recycled HDPE cargo it is always a good idea to ask for a DSC test to check the composition of the granule for production. The effect of an excessive percentage of PP has as a direct consequence the prevention of an effective welding of the contact surfaces that form the bottle. In addition to working on the granule, it would be a good idea if you wanted to use 100% of the recycled raw material, slightly increase the overlap thickness of the two sides of the bottle to favor the correct welding point. 4) The presence of micro or macro holes in a bottle , directly visible through an inspection or, for smaller ones, through the air tightness test, may depend on the presence of impurities inside the granule , when the washing and the filtering of the raw material was not done in a workmanlike manner. Another reason may depend on poor cleaning of the screw of the blowing machine which can accumulate residues of degraded polymer and transport them, subsequently, to the mold. Especially if you use recipes with mineral charge, you may have the problem immediately after changing the recipe between one without charge and one containing it. The use of mixed recipes between virgin and regenerated material can mitigate some of these points but not completely solve any problems if you do not have the foresight to follow the supply chain of the recycled granule.Related articles:HDPE: PRODUCTION OF BOTTLES WITH RECYCLED PLASTIC | SOME ADVICES Automatic translation. We apologize for any inaccuracies. Original articles in Italian.
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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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