Polyethylene terephthalate packaging material

Franz, R., Mauer, A., and Welle, F. (2004). European survey on post-consumer polyethylene terephthalate) (PET) materials to determine contamination levels and maximum consumer exposure from food packages made from recycled PET. Food Addit. Contam. 21, 265-286. 

Nor is it tme that poly(ethylene terephthalate) (PET) and high density polyethylene (HDPE) packaging are hsted as 1 and 2 in the Society of the Plastics Industry (SPI) recycling coding system because they are the most recyclable. The numbers assigned to each plastic in the SPI coding system are purely arbitrary and do not redect the material s recyclabihty. 

Because polyethylene terephthalate crystallizes slowly, it can readily be produced in its amorphous state. This is especially true when it is used in packaging materials, such as thin films and carbonated drink bottles. The final products exhibit high clarity and directionally balanced properties because they lack crystalline regions. 

Polyethylene terephthalate is often used to produce films for food packaging. What properties of this material are critical when designing food packaging ... 

With the exception of ethylene vinyl acetate added in the 1980 s, the list of materials and polymers approved as packaging for food irradiated products has remained static for decades. This article supplies details of the approved list, which includes such polymers as polyethylene terephthalate and polyvinyl chloride. The article provides an update on the latest proactive move to expand the list of packaging materials and polymers approved for the irradiation of foods. The expanded list would include ethylene vinyl alcohol, PVC film, ionomers, nylon 66, 6/12 and copolyesters among others. 

International Life Sciences Institute (2000). Report on Packaging Materials 1. Polyethylene terephthalate (PET) for food packaging applications. ILSI Europe Packaging Material Task Force, Brussels. 

Papachristou, C., Badeka, A., Chouliara, I., Kondyli, E., Kourtis, L., and Kontominas, M. G. (2006a). Evaluation of polyethylene terephthalate as a packaging material for premium quality whole pasteurized milk in Greece. Part II. Storage under fluorescent light. Eur. Food Res. Technol. 224, 237-247. 

Amorphous polyethylene terephthalate) is not suited to welding by these means the material may be modified with glycol to make formings for packaging, and this modified material can be tear-sealed. 

Application Production of polymer-grade terephthalic acid (MTA). MTA is an excellent raw material to produce polyethylene tereph-thalate resin (PET), which is used for engineering plastics, packaging materials—like bottles and other food containers—as well as films. Also, integrated polyester producers use MTA to make various types of fibers. 

Saran (Dow polyvinylidene dichloride) is a tough, chemically resistant plastic available in a variety of forms that are useful in the laboratory. Saran pipe or tubing can easily be welded to itself or sealed to glass and is useful for handling corrosive solutions. Thin Saran film, available commercially as a packaging material, is useful for windows, support films, etc. Mylar (du Pont polyethylene terephthalate) film and other polyester films are also useful for these purposes. Mylar is chemically inert and has excellent electrical properties for electrical insulation and for use as a dielectric medium in capacitors. Much thinner than these are films that can be made in the laboratory by allowing a dilute ethylene dichloride solution of Formvar (polyvinyl acetal) to spread on a water surface and dry. 

R. FRANZ, Programme on the recyclability of food packaging materials with respect to food safety considerations - Polyethylene terephthalate (PET), paper board and plastics covered by functional barriers. Food Additives and Contaminants, 2002, 19(snpplement), 93-110. 

Examples of the use of nanostructured materials for packaging applications have been given in Chaudhry et al. (2008) and references therein. One of the first market entries into the food packaging arena was polymer composites containing clay nanoparticles (montmorillonite). The natural nanolayer structure of the clay particles impart improved barrier properties to the clay-polymer composite material. Some of the polymers which have been used in these composites for production of packaging bottles and films include polyamides, polyethylene vinyl acetate, epoxy resins, nylons, and polyethylene terephthalate. 

Concerns about health effects caused by low levels of residual monomers in PVC and acrylonitrile resins promoted the consideration of condensation polymers such as poly(ethylene terephthalate) (PET) (41). Packaging resins based on acrylonitrile are extraordinarily good barriers that were considered for carbonated beverage bottles. The furor over residual monomers in these materials stunted their growth in spite of improved technology to reduce residuals to barely detectable levels. The step reaction polymer, polyethylene terephthalate(PET) has intrinsically much lower residual monomers in the as-made polymer, and it has become the material of choice for the carbonated beverage market (42). 

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