Properties of linear elastomeric polyurethanes

Abstract

Abstract The viscoelastic properties of some polyester‐urethanes are compared with the properties of other polymers. The behavior observed is anomalous in that these polyurethanes exhibit an unusually high value of modulus well above their T g , unaccounted for by either crosslinking or crystallinity. Various experiments including incorporation of plasticizes of widely varying chemical composition have suggested interpretation of the system as a block copolymer, each block having its own T g . Each of the two types of blocks seems to associate with similar blocks from other molecules.