Thermoplastic Copolyester Elastomers, Their Structural Diversity and Applications

Thermoplastic copolyester elastomers (TPEE) are a category of important industrial polymeric materials, receiving increasing attention in both commercial manufacturing and academic circles. This chapter provides the synthesis, structure, properties and applications of TPEEs. TPEEs belong to the class of thermoplastic elastomers which combine mechanical properties of chemically crosslinked elastomers with those of thermoplastics. Thermoplastic copolyester elastomers are multiblock copolymers of chemically different hard (polyester) and soft (polyether) segments connected by ester linkages. Owing to their segmented structure and a two-phase microstructure, they have superior mechanical properties. The properties of TPEEs depend on the chemical nature and incompatibility of the hard and soft segments, as well as on their weight ratio and respective lengths. TPEEs ranging from soft to hard elastomers can be obtained by varying the hard or soft segment content, the length of the soft segments and/or the degree of crystallinity of the hard segments. Due to the high performance properties of TPEEs, an extensive section on mechanical, thermal and chemical properties is presented. The recent developments of TPEE materials, such as nanocomposites and blends, as well as biodegradable TPEEs, are also addressed. Processing, recycling possibilities and the future trends in TPEEs development are also discussed