Study of the microstructure, foaming property and cyclic compression performance of poly(ether-block-amide) foams fabricated by supercritical CO2 foaming

Abstract

This paper systematically explored the effects of molecular structure on the foaming behavior of poly(ether-block-amide) (PEBA) and its influence on foam cyclic compression properties. It was demonstrated that increasing the hard segment (HS) content of PEBA not only improved crystallization and melting strength, but also narrowed the melting peak and shifted it to higher temperatures. In contrast to other thermoplastic elastomers such as TPU, PEBA with a higher HS content showed a lager foam expansion ratio but a narrower foaming window. Increasing HS content improved compression strength but deteriorated resilience of PEBA foams. As the expansion ratio increased to 5-fold, there was no significant reinforcing effect of HS on strength and modulus of PEBA foams, while the resilience of the foams increased constantly with decreasing HS content and increasing expansion ratio.