Fully substituted cyclopolysiloxanes and their use for making organosilicon polymers
AssigneeHercules Incorporated
InventorDe-Kai Loo
Life of this patent
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Abstract
Disclosed are organosilicon crosslinked polymers and crosslinkable prepolymers that are the reaction product of (a) a cyclic polysiloxane in which each silicon atom is substituted with (i) a saturated, substituted or unsubstituted alkyl or alkoxy group or a substituted or unsubstituded aryl or aryloxy group, and (ii) a substituted or unsubstituted hydrocarbon group having at least one carbon-carbon double bond that is reactive in hydrosilation, (b) at least one organosilicon compound having at least two .tbd.SiH groups, and optionally (c) a hydrocarbon polyene having at least two nonaromatic carbon-carbon double bonds that are reactive in hydrosilation. A process for preparing the polymers and prepolymers and for preparing the cyclic polysiloxanes is also disclosed.
Claims20
An organosilicon crosslinked polymer or crosslinkable prepolymer that is the hydrosilation reaction product of:
- (a) a cyclic polysiloxane having the formula ##STR7## where R is saturated, substituted or unsubstituted alkyl or alkoxy group or a substituted or unsubstituted aryl or aryloxy group, R' is a substituted or unsubstituted hydrocarbon group having at least one nonaromatic carbon-carbon double bond that is reactive in hydrosilation, and n is 3, or 3 and 4, and
- (b) at least one organosilicon compound having at least two .tbd.SiH groups selected from the group consisting of (1) cyclic polysiloxanes and (2) tetrahedral siloxysilanes, said hydrosilation reaction being carried out in the presence of a hydrosilation catalyst.
A process for preparing a crosslinked polymer or a crosslinkable prepolymer comprising reacting:
- (a) a cyclic polysiloxane having the formula ##STR10## where R is a saturated, substituted or unsubstituted alkyl or alkoxy group or a substituted or unsubstituted aryl or aryloxy group, R' is a substituted or unsubstituted hydrocarbon group having at least one nonaromatic carbon-carbon double bond that is reactive in hydrosilation, and n is 3, or 3 and 4, and
- (b) at least one organosilicon compound having at least two .tbd.SiH groups selected from the group consisting of (1) (1) cyclic polysiloxanes and (2) tetrahedral siloxysilanes, in the presence of a hydrosilation catalyst.
Dependencies are inferred from the claim text.