Poly food-packaging

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Considerable interest has been shown ia poly(ethylene oxide) for diverse appHcations ia food, drug, and cosmetic products. Such uses fall within the scope of the Federal Food, Dmg, and Cosmetic Act. The U.S. FDA has recognized and approved the use of poly(ethylene oxide) for specific food and food packaging uses. USP/NF-grades of Polyox water-soluble resins (Union Carbide Corp.) are available for pharmaceutical appHcations. 

Nearly all uses and appHcations of benzyl chloride are related to reactions of the active haUde substituent. More than two-thirds of benzyl chloride produced is used in the manufacture of benzyl butyl-phthalate, a plasticizer used extensively in vinyl flooring and other flexible poly(vinyl chloride) uses such as food packaging. Other significant uses are the manufacture of benzyl alcohol [100-51-6] and of benzyl chloride-derived quaternary ammonium compounds, each of which consumes more than 10% of the benzyl chloride produced. Smaller volume uses include the manufacture of benzyl cyanide [140-29-4], benzyl esters such as benzyl acetate [140-11-4], butyrate, cinnamate, and saUcylate, benzylamine [100-46-9], and benzyl dimethyl amine [103-83-8], and -benzylphenol [101-53-1]. In the dye industry benzyl chloride is used as an intermediate in the manufacture of triphenylmethane dyes (qv). First generation derivatives of benzyl chloride are processed further to pharmaceutical, perfume, and flavor products. 

IX lists the results of some of these experiments, comparing the nitrile materials with polyethylene, the most widely used plastic container material, and poly (vinyl chloride), which is being used for a number of food packaging applications. Note that in all instances there is an order of magnitude difference between the Lopac container and the other two. For flavorants, which are usually present in very low concentrations, this dilute solution test is probably more significant than a standard permeability test which only measures weight losses of the pure ingredient. 

The commercial polymeric films (Table I) that are used as the outside layer of multilayered materials for thermoprocessed food packaging are poly(ethylene terephthalate), polyiminocaproyl, or polypropylene. The other five films listed in Table I or polypropylene are used for the food-contacting layer. 

Both thermosets and thermoplastics are used as food-contact materials, though thermoplastics predominate in this appfication. Examples of the former are phenol- and urea-formaldehyde, while probably the best known example of the latter is low-density poly(ethylene). Other linear polymers are used include high-density poly(ethylene), poly(propylene), and PVC, all of which find quite extensive use. Polymers for food packaging may be in the form of films and other flexible items, or in the form of rigid containers, such as clear drinks bottles or opaque cartons for dairy products. 

A GC-IR-MS system with library search capability has been used to effectively identify the pyrolysis products of polybutadiene and the antioxidant additive 2,6-di-f-butyl-4-methylphenol [199]. Paper for food packaging was analysed by P T (at 100 °C) combined with /i-GC-UV. No specific applications of /rGC-UV to poly-mer/additive analysis have as yet been reported. 

Polyethylene food packaging, 18 40-42 Poly(ethylene glycol) (PEG), 12 658 gas chromatography stationary phase, 4 617t... 

The primary crystalline polymer based on CHDM is the terephthalate, poly(1,4-cyclohexylenedimethylene terephthalate) (PCT). This polyester was originally developed for fiber applications but has since found wider utility as a reinforced polymer for injection molding and (when copolymerized with a small amount of isophthalic acid) as a material for crystallized food packaging trays. The key property of PCT which sets it apart from other thermoplastic polyesters in these latter applications is its melting point. 

Uses Synthetic fibers and adhesives chemical intermediate in vinylidene fluoride synthesis production of poly(vinyl dichloroethylene) and LLl trichloroethane comonomer for food packaging, coating resins, and modacrylic fibers. 

Copolymers of ethylene and norbomene exhibit excellent transparency, high moisture barrier, high strength and stiffness, and low shrinkage. In comparison to poly(ethylene) (PE) and polypropylene) (PP), they show a very low gas permeability. They are used for blister packaging in pharmacy applications and for flexible films for food packaging. Multilayer films consisting of PP outer layers and a cyclic olefin copolymer are in use. 

Poly(vinyl acetate) polymers are environmentally friendly because they easily biodegrade. Poly(vinyl acetate) may be hydrolyzed to poly(vinyl alcohol) which is then assimilated by naturally occurring organisms. In the use of emulsion polymers, the associated components (stabilizers, initiators, etc) should be scrutinized for their effect on the environment. Poly(vinyl acetate) is nontoxic and is approved by the U.S. FDA for food-packaging (qv) applications (CFR 176.170,175.105). Components in the emulsion polymer system which may migrate from the film into the food may impact the approval of the total package. In food applications the impact on odor and taste of residual low molecular weight components may be important in the selection of a product for use. 

Here we report the use of a readily prepared polymer immobilised TEMPO as a catalyst for alcohol oxidations.15 It was derived from a commercially available oligomeric, sterically hindered amine, poly[[6-[(l,l,3,3-tetramethylbutyl)amino]-l,3,5-triazine-2,4-diyl] [2,2,6,6-teramethyl-4-piperidinyl)-imino]-1,6-hexane-diyl[(2,2,6,6-tetramethyl-4-piperidinylimino]], better known as Chimassorb 944 (MW 3000 see figure 3 for structure). This compound is used as an antioxidant and a light stabiliser for plastics. It contributes significantly to the long-term heat stability of polyolefins and has broad approval for use in polyolefin food packaging.16... 

Choi, W.Y., Lee, C.M., and Park, H.J. (2006). Development of biodegradable hot-melt adhesive based on poly-[epsilon]-caprolactone and soy protein isolate for food packaging system. LWT Food Sci. Technol. 39(6), 591-597. 

R. FRANZ, A. MAUER, F. WELLE, European survey on post-consumer poly(ethylene terephthalate) materials to determine contamination levels and maximum consumer exposure from food packages made from recycled PET, Food Additives and Contaminants, 2004, 21(3), 265-286. 

Polymers from this class can be used for different practical purposes. For example, poly(ethylene-co-carbon monoxide) has better barrier properties for food packaging material than polyethylene, which is permeable for hydrophobic compounds used as flavors. Other copolymers can be used as plasticizers for nitrile rubber. 

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