ORGANOPOLYSILOXANE / POLYUREA / POLYURETHANE BLOCK COPOLYMERS

摘要

Organopolysiloxane/polyurea/polyurethane block copolymer elastomers exhibiting improved physical properties are prepared by reacting diisocyanates with aminoalkyl-functional organopolysiloxanes containing substantially no cyclic siloxanes, prepared by reacting a cyclic silazane with a bis(hydroxy)-organopolysiloxane. Traditional hydroxyl and amino-functional chain extenders may be reacted as well, to produce a wide range of block copolymer elastomers.