Synthetic crystallizable elastomers

The copolymerization of butadiene in trans configuration with suitable comonomers represents a second route for obtaining a wide range of strain induced crystallizable elastomers, with melting point tailorable in a wide range of temperatures. These copolymers can be used, in particular, in blends with other crystallizable rubbers (e.g. synthetic cis-l,4-polyisoprene) in order to improve their "green strength". 

Polychloroprene, developed and sold under the trade name Neoprene by DuPont, was the first commercially successful synthetic elastomer. It is produced by free-radical emulsion polymerization of chloroprene (2-chloro-l,3-butadiene). The commercial material is mainly /raw5-l,4-polychloroprene, which is crystallizable. 

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