Curable compositions comprising organopolysiloxane-polyoxyalkylene block copolymers and cured products obtained from the compositions
US5138009A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 20, 1991 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | Mar 20, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L83/12
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A curable composition comprises an organopolysiloxane-polyoxyalkylene block copolymer terminated at both ends of a molecular chain with a lower aliphatic unsaturated group and consists essentially of organopolysiloxane units having a main chain of the formula, (R.sup.1 R.sup.2 SiO)m, and polyoxyalkylene units of the formula, (R.sup.3 O)n. The organopolysiloxane units and the polyoxyalkylene units are bonded through R.sup.1 R.sup.2 SiR.sup.4 groups, wherein R.sup.1 and R.sup.2 independently represent an unsubstituted or substituted monovalent hydrocarbon group except for an aliphatic unsaturated group, R.sup.3 and R.sup.4 independently represent a divalent hydrocarbon group, and m and n are, respectively, defined integers. The composition further comprises an organohydrogenpolysiloxane having at least two .tbd.SiH groups in one molecule and a curing agent therefor. A cured product obtained from the composition is a silicone rubber elastomer having properties inherent to the silicone rubber but is hydrophilic in nature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.