Editing Thermoplastic (section)

==Polypropylene==
[[Polypropylene]] (PP) is useful for such diverse products as reusable plastic food containers, microwave- and dishwasher-safe [[plastic container]]s, [[diaper]] lining, [[sanitary pad]] lining and casing, ropes, carpets, plastic moldings, piping systems, [[car batteries]], insulation for electrical cables and filters for gases and liquids. In medicine, it is used in [[hernia]] treatment and to make heat-resistant medical equipment. Polypropylene sheets are used for stationery folders and packaging and clear storage bins. Polypropylene is defined by the recyclable plastic number 5. Although relatively inert, it is vulnerable to ultraviolet radiation and can degrade considerably in direct sunlight. Polypropylene is not as impact-resistant as the polyethylenes (HDPE, LDPE). It is also somewhat permeable to highly volatile gases and liquids.