Cryodilation of thermoplastic PEBA elastomers

PEBA block copolymers, poly(ether‐block‐amide), containing low concentrations of polyamide are thermoplastic elastomers. These materials, when strained at room temperature and then relaxed, exhibit dilation during cooling to low temperatures (ca.–10°C). This effect, of the order of 5–15%, depending on the concentration of the different blocks, is due to oriented crystallization of the soft polyether segments.