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Polymeric barrier containers, packaging

An essential requirement for the use of polymeric barriers in food packaging is the absence of any additive or residual monomers which can transfer potentially toxic components in any way to the contents of the package and impart an off-flavor to the product or present a health hazard. They must have little or no extractives which is particularly important to avoid odor or taste being imparted to food in the coated container. A variety of special purpose additives, which must be acceptable for use in food-contact applications, are used in coating systems. These additives include pigment dispersants, suspension agents, defoamers, emulsifiers, and rust prevention concentrates. [Pg.311]

Copolymers of acrylonitrile and methyl methacrylate (115) and terpolymers of acrylonitrile, styrene, and methyl methacrylate (116,117) are used as barrier polymers. Acrylonitrile copolymers and multipolymers containing butyl acrylate (118—121), ethyl acrylate (122), 2-etliylliexyl acrylate (118,121,123,124), liydroxyethyl acrylate (120), vinyl acetate (119,125), vinyl ethers (125,126), and vinylidene chloride (121,122,127—129) are also used in barrier films, laminates, and coatings. Environmentally degradable polymers useful in packaging are prepared from polymerization of acrylonitrile with styrene and methyl vinyl ketone (130). Table 5 gives the structures, formulas, and CAS Registry Numbers for several comonomers of acrylonitrile. [Pg.196]

Most aseptic foods are packaged in a variety of polymeric materials. The plastic polymers used in aseptic packages are either in a pure or a coextruded form to optimize barrier properties. These plastics are not as inert as metal and glass containers resulting in a shorter shelf life for laminated packages when compared to metal and glass containers. [Pg.319]

Polyacrylonitrile copolymers are also used in barrier resins for packaging. One such resin contains at least 70% acrylonitrile and often methyl acrylate as the comonomer. The material has poor impact resistance and in one industrial process the copolymer is prepared in the presence of about 10% butadiene-acrylonitrile rubber by emulsion polymerization. The product contains some graft copolymer and some polymer blend. In another process the impact resistance of the copolymer is improved by biaxial orientation. The package, however, may have a tendency to shrink at elevated temperature, because the copolymer does not crystallize. [Pg.259]

In order to tap the commercial applications of LCP in packaging, processing must achieve efficient use of the high-performance polymer. There are many high value polymers and other materials that are used in thin layers. A prime example is ethylene vinyl alcohol (EVOH), a super barrier material used as a thin layer in coextruded film and multilayer containers such as ketchup bottles. Other examples are coatings, such as metal, glass, and polymeric coatings. LCP used in thin multilayer constructions should compete well with these other materials. [Pg.345]


See other pages where Polymeric barrier containers, packaging is mentioned: [Pg.183]    [Pg.273]    [Pg.257]    [Pg.165]    [Pg.306]    [Pg.307]    [Pg.12]    [Pg.24]    [Pg.372]    [Pg.285]    [Pg.94]    [Pg.372]    [Pg.354]    [Pg.146]    [Pg.2235]    [Pg.137]    [Pg.353]    [Pg.184]    [Pg.98]    [Pg.233]    [Pg.228]    [Pg.306]    [Pg.118]    [Pg.334]    [Pg.184]    [Pg.299]    [Pg.299]    [Pg.308]    [Pg.311]    [Pg.312]    [Pg.327]    [Pg.327]    [Pg.336]    [Pg.703]    [Pg.2898]    [Pg.5784]    [Pg.170]    [Pg.563]    [Pg.162]    [Pg.1044]    [Pg.385]   


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