Ionomeric blends. IV. Miscibility of urethane elastomers with styrene–styrene sulfonic acid copolymer

Blends were prepared from two kinds of urethane elastomers, containing 1,4‐butanediol or 3,3′‐dichloro‐4,4′‐diamino‐diphenyl‐methane as chain extenders, with lightly sulfonated polystyrenes. Dynamic mechanical studies show that strong interactions occur between the sulfonic acid and the urethane or urea moieties on the polyurethane chains. These strong interactions are clearly seen in the composition dependence of the loss tangent peaks (due to the glass transitions) for both the high temperature and the low temperature glass transitions of the blends. They are further confirmed by model studies.