Synthesis and properties of segmented poly(hydroxyether‐siloxane)

Segmented or block poly(hydroxyether‐siloxane) copolymers were synthesized by both a monomer‐oligomer or an oligomer‐oligomer synthetic approach. Perfectly alternating sequence distributions were obtained from the monomer or oligomer(s) bearing mutually reactive end groups, and the hydroxyether linkages are formed simultaneously with the growth of the second block. Differential scanning calorimetry (DSC), Dynamic Mechanical Thermal Analyzer (DMTA), and small angle X‐ray scattering (SAXS) results indicated that microphase separated morphologies were achieved for each of the copolymers, even those structures synthesized by the monomer‐oligomer route. The mechanical properties of the networks ranged from a rubber toughened thermoplastic to a thermoplastic elastomer and depended on which phase was predominantly continuous. Copyright © 1989 Hüthig & Wepf Verlag