Packaging applications generally

Table I shows the chemical composition limits of various aluminum alloys presently used for packaging applications (3). In general, these alloys have good corrosion resistance with most foods. However, almost without exception, processed foods require inside enameled containers to maintain an acceptable shelf life (4, 5). Moreover, when flexible foil packages are used for thermally processed foods, the foil is laminated to plastic materials that protect it from direct contact with the food and also provide heat sealability as well as other physical characteristics (6,7).

General purpose PS and HIPS are used in food packaging applications. In some packaging configurations, with no direct contact of a surface with the polymer the migration of residual styrene monomer via the vapor-phase with subsequent absorption into the food is believed to be a significant mechanism of accumulation. 

The physical properties and melt processing of PLA are similar to those of conventional packaging resins. It may thus be used as a commodity resin for general packaging application. In many aspects the basic properties of PLA lie between those of crystal PS and PET [ 14]. When plasticized by its own monomer lactic acid, PLA becomes increasingly flexible so that products that mimic PVC, LDPE, LLDPE, PP, and PS can be prepared [15]. Possible applications are espe-... 

The main types of NatureWorks PLA that are available for packaging applications include general purpose film grades, extrusion coating, extrusion and thermoforming grades and injection stretch blow moulding. 

Phthalate plasticisers have historically served as the preferred plasticisers to impart flexibility to PVC and several other polar polymers. They provide a desirable balance of cost and performance properties. Their acceptable and safe use is unmatched in medical appliances, food processing and packaging applications, as well as many other end uses. Potential alternatives do not have the historical record of acceptable performance found with phthalate plasticisers. Nevertheless, the Precautionary Principle has caused certain segments of society to clamour for alternatives to phthalate plasticisers. Known non-phthalate plasticisers are reviewed, and comparisons to the traditional General Purpose (GP) phthalate plasticisers are provided General Purpose plasticisers are those that impart optimum overall performance properties in PVC at lowest cost. 6 refs. USA... 

It is generally known that only a very limited number of packaging materials such as glass or metal provide absolute protection properties concerning the penetration of chemical compounds from layers behind or from the environment. In the case of multi-layers with plastics materials as functional barriers there occurs, in most cases to a certain extent, an unavoidable mass transfer from the plastics layers into the product. This must be understood as a functional quantity which, however, must comply with food regulations. Therefore it is necessary firstly to understand functional barrier characteristics and mechanisms and, secondly, to define the functional barrier efficiency in relation to food safety and to establish appropriate test methods. This is especially important with those food packaging applications where recycled plastics are covered by plastics functional barriers. 

Buonocore GG, Del-Nobile MA, Panizza A, et al. A general approach to describe the antimicrobial agent release from highly swellable films intended for food packaging applications. J Controlled Release 2003 90(1) 97—107. 

In some applications, it is useful to incorporate nonplastic substances into a plastic object, to reduce its cost or improve its performance in some way. Fillers are typically used to lower the cost of the plastic, and generally consist of minerals of some kind. Reinforcements are often more expensive, per unit mass or volume, than the plastics, but provide improvement in properties such as strength and/or rigidity. They usually consist of either organic or inorganic fibers. Use of fillers and reinforcements is less common in packaging applications than in uses such as automotive components or housewares, but is sometimes significant. In addition, these additives are more commonly used with thermoset polymers than with thermoplastics. 

Regulatory Approval Food additive regulations issued by the Food and Drug Administration (FDA) permit use of eellulose acetate in specific food packaging applications. Cellulose acetate (CA) is Generally Recognized As Safe (GRAS) for use in paper and paperboard in contact with food, and has been previously sanctioned for use in film in food-contact applications.f ... 

Welcome to the Second Edition of Film Properties of Plastics and Elastomers A Guide to Non-Wovens in Packaging Applications. This edition presents an overview of film properties, including physical, optical, electrical, and permeation properties, as well as regulatory information where relevant to the use of different materials presented. These material chapters present the quantitative data in tabular and graphical formats accompanied by a qualitative discussion regarding the general film properties and film applications. 

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