Poly packaging material

In the past few years many changes have occurred in the packaging materials utilized for distilled spirits. Traditionally, distilled spirits have been packed primarily in glass containers of approved ATF sizes. Over the last 5—10 years, plastic containers, primarily poly(ethylene terephthalate) (PET), have been utilized by increasing numbers of distillers. Because of environmental concerns, the last two years have seen a change back to glass on some of these package sizes. However, the 50 mL miniature bottie continues to be primarily packed in PET plastic containers. 

Packaging materials which have a smooth, impervious surface, free fi cm crevices or interstices, such as cellulose acetate, polyethylene, polypropylene, poly vinylchloride, and metal foils and laminates, all have a low surface microbial count. Cardboard and paperboard, unless treated, carry mould spores of Cladosporium spp., Aspergillus spp. md Penicillium spp. and bacteria such 2 Bacillus spp. sn.dMicrococcus spp. 

The disadvantages of all biochemical routes is the lack of variable tacticity in the polymer and, even more important, the need for time-consuming purification. PHB materials of feasible properties are only achieved with high production costs. In the 1990s, ICl sold a copolymer of 3-HB and 3-HV (BIOPOL) for about 10-20 /kg whereas the price of PP was less than 2 /kg. Therefore, a fermentative synthesis is feasible for smaller applications but not cannot compete with packaging materials such as poly(olefin)s [43 5] (Fig. 10). 

Polymer-coated heat sealable packaging materials are composed of several layers (64). The material includes a fiber base of packaging paper or packaging board, an outer polymeric heat sealing layer, such as low density poly(ethylene) (LDPE), and an inner polymeric... 

In addition, further layers, e.g., polymeric oxygen barrier layers, such as ethylene vinyl alcohol or poly(amide) layers, can be incorporated into the packaging material. A most simple structure for the build up of the layers and an example for a packaging article are shown in Figure 2.4. 

The majority of packaging plastic materials consists of polyolefins and vinyl polymers, namely polyethylene (PE), polypropylene (PP), polystyrene (PS) and poly(vinyl chloride) (PVC). Obviously, these polymers have many other applications not only as packaging materials. Chemically they are all composed of saturated hydrocarbon chains of macro-molecular size their typical thermal decomposition pathway is free radical one initiated by the homolytic scission of a backbone carbon-carbon bond. In spite of the basic similarity of the initial cleavage, the decomposition of the hydrocarbon macroradicals is strongly influenced by fhe nafure of the side groups of the main chain. 

Reports dealing with the technical application of polymeric AO are concerned mostly with aromatic amines. Excellent results in the stabilization of SBR or NBR articles in engineering applications were obtained with Chemigum HR (86) [77]. Oligomeric 2,2,4-trimethyl-l,2-dihydroquinoline (100) has been used successfully for many years in stabilization of vulcanized rubbers. Both 86 and 100 are efficient AO. The imporance of the application of polymeric phenolic AO for the stabilization of packaging materials for foods may be exemplified [114] The absorption of Poly AO-79 (97) in the gastrointestinal tract was studied with relationship to the M of the AO ... 

Although glass containers are very suitable for Hb packaging, flexible plastic containers constructed from materials such as poly(ethylene-vinyl acetate) (EVA) are most widely used. The plastic packaging material must be carefully selected. Hemoglobin, like other proteins, is lipophilic and can facilitate extraction of low molecular weight lipophilic substances, such as the plasticizers used in poly(vinyl chloride) containers. 

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. 

Cryovac [Grace], TM for a light, shrink-film, transparent packaging material based on poly-vinylidene chloride. Used especially for meats and other perishables. 

Weng, Y.M., Chen, M.J., and Chen, W. 1999. Antimicrobial food packaging materials from poly(ethylene-co-methacrylic acid). Lebensmittel-Wissenschaft und-Technologie 32 191-195. 

The principal uses of poly(ethylene terephthalate) film are electrical, particularly in capacitors, as slot liners for motors and for recording tape. Its high strength and dimensional stability have led to a number of drawing office applications. The film is also a useful packaging material whilst metallised products have a number of uses as a decorative material. 

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