Publisher's Synopsis
Styrenic copolymers are engineering thermoplastics. The most important are styrene-acrylonitrile copolymer (SAN) and acrylonitrile-butadiene-styrene terpolymer (ABS). Other monomers can also be used with styrene including methyl methacrylate and butadiene. Blends of styrenic copolymers with other thermoplastics are also becoming established in the market place, the most common are blends of ABS with polycarbonate or polyamide. The main market sectors for these materials are automotive and transport, electrical and electronics, and information technology applications. In Europe alone these three market sectors accounted for around 650 kt of styrenic copolymers in 2001. Applications in these industries are discussed in this review. Styrenic copolymers have good surface quality, high dimensional stability and constant mechanical properties almost up to the softening temperature. This report discusses the different types of styrenic copolymers available in the market place today, their properties and applications. The market situation is discussed. These materials fall between the commodity thermoplastics and the high-performance polymers such as polysulfone. continue because of growth in key markets, particularly the Far East. The current total global capacity for producing styrenic copolymers is around 6,500 kt, and the number of producers is limited. The chemistry of these materials is outlined, together with a summary of manufacturing methods. By varying the monomer content of these materials the properties can be adapted. For example for SAN, increasing the content of styrene improves stiffness, clarity and processability. The presence of an elastomeric phase in ABS improves the impact resistance for engineering applications. Special purpose grades include high-temperature, clear and weather-resistant materials. Styrenic copolymers are increasingly being used in blends and alloys, and the properties of the styrenic polymers tend to predominate. The morphology, manufacture and properties of key materials are described here. Styrenic copolymers can be processed by all the common methods including injection moulding, extrusion and blow moulding. techniques, multi-component injection moulding and co-extrusion. This review is extensively referenced in the text. It is accompanied by summaries of the cited papers from the Rapra Polymer Library database (formerly known as Rapra Abstracts). These papers are indexed to allow the reader to search for information on specific topics.
