Polystyrene packaging material

Linssen, J. P. H., Janssens, J. L. G. M., Reitsma, J. C. E., and Roozen, J. P. (1991). Sensory analysis of polystyrene packaging material taint in cocoa powder for drinks and chocolate flakes. Food Addit. Contam. 8(1), 1-7. 

Selecting appropriate polystyrene packaging materials for specific packaging applications... 

Styrene can cause off-flavors in food products packed in polystyrene packaging materials. Each food product has a different sensitivity to styrene off-flavors and thus each food package system needs to be evaluated individually. The formation of styrene off-flavor in a given package/product system can be estimated a priori given the styrene threshold concentration in the food, the initial residual styrene monomer concentration in the packaging material and the desired shelf life. If this information is not readily available then accelerated storage tests followed by a sensory comparison can be carried out to evaluate the potential of off-flavor formation in the product. 

Expanded polystyrene bead mol ding products account for the largest portion of the drinking cup market and are used in fabricating a variety of other products including packaging materials, iasulation board, and ice chests. The iasulation value, the moisture resistance, and physical properties are inferior to extmded boardstock, but the material cost is much less. 

Because of the excellent gas barrier properties, EVOH is of interest as a packaging material. However, because of its high water absorption it is usually used as an internal layer in a co-extruded film, sheet, bottle or tube. For example, the system HDPE-EVOH-EVA may be used as a barrier film for packaging cereals, and the system polystyrene-EVOH-polystyrene for packaging coffee and cream, whilst the system polystyrene-EVOH-polyethylene has the additional advantage of heat scalability. 

STYR0P0R, BASF - polymerization of styrene monomer in suspension in the presence of pentane as the blowing agent. Manufacture of new insulating packaging materials, etc. Suspension polymerization of crystal polystyrene in Ludwigshafen. 

Extruded polystyrene foam sheet is primarily produced in a single screw tandem extrusion line. Primary application of foam sheet is as a packaging material in items such as disposable dishes and food containers, trays for meal, poultry and produce products, and egg canons. 

Polystyrene is made by radical polymerization and is atactic and amorphous. Incorporation of small air bubbles produces a foam (Styrofoam) that finds a major use in packaging materials and insulation. 

Given the initial concentration of styrene residual monomer in the packaging material, the styrene threshold concentration in the product and the desired shelf life of the product one can estimate whether or not a given polystyrene material will cause taints in a given packaging application. 

Polystyrene is an amorphous, white and brittle plastic. Polystyrene has many applications due to its rigidity. Polystyrene is used for making products such as toys, display boxes, packaging material, egg cartons and styrofoam. 

Thus far, we have considered addition polymerization routes - either catalyzed or uncatalyzed. Although this is sufficient to describe the synthesis of common packaging materials such as polyethylene, polypropylene, polystyrene, etc., other classes of polymers such as nylon, PETE, and polyacrylamide are generated through step-growth mechanisms. Although the synthetic pathway for these polymers is more straightforward than addition polymerization, there are many intricate considerations that affect overall polymer properties. 

ILSl Europe Report Series Packaging Materials 1. Polyethylene terephthalate (PET) for food packaging applications 2. Polystyrene for food packaging applications 3. Polypropylene for food packaging applications 4. Polyethylene for food packaging applications 5. Polyvinyl chloride (PVC) for food packaging applications. 

Figure 1.10 Polystyrene foam rapidly became the packaging material of choice for everything from medical instruments to engines (courtesy of BASF, Ludwigs-hafen)...

Polystyrene loose-fill packaging material used in US Federal Government applications must meet US Government Specification PPP-C-1683 (12/5/ 1988), Cushioning Material, Expanded Polystyrene Loose-Fill Bulk (for Packaging Application) . Compliance with eight properties is the basis for this... 

Other styrenic polymer foams were developed in the mid-1950s through the early 1960s. Examples are molded expanded polystyrene foam (MEPS), extruded polystyrene foam sheet, and expanded polystyrene loose-fill packaging material. 

Two of the most important food packaging materials using polystyrene resins are oriented polystyrene sheet (OPS) and polystyrene foam sheet. Together, OPS and polystyrene foam sheet packaging account for nearly 40 % of the polystyrene resins used in food packaging applications in North America. 

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