High-impact polystyrene food containers

High-impact polystyrene (HIPS) is produced by polymerizing styrene in the presence of a rubber, usually poly(l,3-butadiene). HIPS has improved impact resistance compared to polystyrene and competes with ABS products at low-cost end applications such as fast-food cups, lids, takeout containers, toys, kitchen appliances, and personal-care product containers. HIPS as well as ABS and SMA are used in physical blends with other polymers, such as polycarbonates, polyesters, and polyamides, to improve impact resistance (Sec. 2-13c-3). 

Expanded polystyrene (EPS) articles are made using high impact polystyrene formulations with incorporation of a blowing agent (this is usually a volatile solvent such as pentane). Often, EPS containers will have a crystal polystyrene skin applied to the food contact surface to act as a barrier between food and container. Applications of EPS include thermoformed packaging for eggs, meat, fish and fast food trays. Substances typically used in the manufacture of polystyrene are given in Table 10.3. 

High impact polystyrene (HIPS) is synthesized by emulsion polymerization of styrene in styrene-butadiene latex. The higher impact characteristics of HIPS make it suitable for use in the manufacture of sheets, food containers, window frames, household goods, etc. 

High impact polystyrene (HIPS) This rubber-modified composite typically contains 1-10 wt.% mbber, generally polybutadiene, to give added toughness. It is also used in many applications including food packaging and molded parts. 

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