... maintain maximum endurance, elasticity and plasticity of PU elastomer. HERPhysical Properties of HER AppearanceWhite crystal powderMolecular weight198.22Hydroxyl ... It also offers minimum shrinkage. Besides of those common advantages of aromatic family chain extenders, HER avoids the ... , low melting point and easy handling etc. Typical uses of HER include seal, mud pipeline lining, skating wheel, ...