Heat-resistant silicone-polyurethane and a process for its synthesis

摘要

A new type heat-resistant silicone-polyurethane, which contains polysiloxane chain units of the general formula (II) with diisocyanato end groups and with polyurethane bonds in the chain
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ -OCN-Z-NH-CO-O-X-O-CO-(NH-Z-NH-CO-O-X-O-) m -CO-NH-Z-NCO-€ƒ€ƒ€ƒ€ƒ€ƒ(II)
- wherein X is the molecular fragment containing the siloxane chain, Z is the molecular fragment containing the alkyl chain, m is an integer between 1 and 20 - and/or polysiloxane chain units of the general formula (IV) with diisocyanato end groups and with polyurethane bonds in the chain
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ -OCN-X-NH-CO-O-Z-O-CO-(NH-X-NH-CO-O-Z-O-) m -CO-NH-X-NCO-€ƒ€ƒ€ƒ€ƒ€ƒ(IV)
- wherein X is the molecular fragment containing the siloxane chain, Z is the molecular fragment containing the alkyl chain, m is an integer between 1 and 20 - as crossed-linked polymer units and a process for the synthesis of thereof.