6 - Thermoplastic Elastomers

Abstract

Publisher Summary Thermoplastic elastomers have become a significant part of the elastomers industry since they were first produced about 55 years ago. Thermoplastic elastomers can be processed using conventional plastics techniques, such as injection molding and extrusion; scrap can be recycled. At higher temperatures, the properties of thermoplastic elastomers are usually not as good as those of the conventional vulcanized rubbers. Applications of thermoplastic elastomers are, therefore, in areas where these properties are less important. Thermoplastic elastomers can be divided into six basic types: styrenic thermoplastic elastomers, multiblock copolymers, hard polymer-elastomer combinations, graft copolymers, ionomers, and core–shell morphologies. Almost all thermoplastic elastomers contain two or more distinct polymeric phases and their properties depend on these phases being finely and intimately mixed. In some cases, the phases are not chemically bonded, but in others they are linked together by block or graft copolymerization. The worldwide annual production of thermoplastic elastomers of all types is estimated at about 2,500,000 metric tons in 2005 with a value of almost $12 billion. Production is expected to rise to about 4,200,000 metric tons in 2014. This is equivalent to an annual growth rate of about 5.3%. In 2009, North America consumed about 25% of this amount, Western Europe about 20%, and China about 33%. Japan and other Asia/Pacific countries accounted for most of the rest. The thermoplastic polyurethanes and the thermoplastic polyesters together made up another 20%. Major end uses are transportation, footwear, industrial goods, wire insulation, medical, adhesives, and coatings.