Room temperature curing polysiloxane compositions
AssigneeToshiba Silicone Co., Ltd.
InventorsMitsuyoshi Hashimoto, Kiyoshi Hosokawa, Tsuneo Motegi
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Abstract
A storage-stable, room-temperature-curing polysiloxane composition comprising polydiorganosiloxane having silanol terminal radicals and from 0.5 to 25 parts by weight, per 100 parts by weight of said polydiorganosiloxane, of a curing agent containing from 1.5 to 100 wt. % of silane having the formula ##STR1## wherein R.sup.3 is a substituted or unsubstituted hydrocarbon radical, Q is alkylene or alkylidene, R.sup.4 is ##STR2## wherein R.sup.6 and R.sup.7 are substituted or unsubstituted hydrocarbon radicals, R.sup.5 is hydrogen or a substituted or unsubstituted hydrocarbon radical, n is 1 or 2, a is 0 or 1 and b is 1, 2, 3 or 4, and the balance of the curing agent is tri-acyloxysilane.
Claims21
A room-temperature-curable polysiloxane composition consisting essentially of:
- (A) polydiorganosiloxane having silanol terminal radicals, said polydiorganosiloxane having a viscosity of 500 to 200,000 cSt at 25.degree. C.,
- (B) from zero to 24.625 parts by weight, per 100 parts by weight of component (A), of acyloxy radical-containing organosilicon component selected from the group consisting of first compounds having the formula:
- ##STR20## wherein R.sup.1 and R.sup.2, which can be the same or different, each is a monovalent, substituted or unsubstituted hydrocarbon radical,
- partial hydrolyzates of said first compounds and mixtures thereof, and
- (C) from 0.0075 to 25 parts by weight, per 100 parts by weight of component (A), of organosilane component selected from the group consisting of second compounds having the formula:
- ##STR21## wherein R.sup.3 is a monovalent, substituted or unsubstituted hydrocarbon radical, n is 1 or 2, Q is alkylene or alkylidene and when n is 2, Q can be the same or different, R.sup.4 is an ester bond-containing radical having the formula:
- ##STR22## wherein R.sup.6 and R.sup.7 are monovalent, substituted or unsubstituted hydrocarbon radicals, R.sup.5 is a monovalent radical selected from the group consisting of hydrogen and monovalent, substituted or unsubstituted hydrocarbon radicals, a is 0 or 1 and b is an integer of 1, 2, 3 or 4, partial hydrolyzates of said second compounds and mixtures thereof, the sum of components (B) and (C) being 0.5 to 25 parts by weight per 100 parts by weight of component (A), the amount of component (B) being from zero to 98.5 wt. % based on the sum of components (B) and (C), and the amount of component (C) being at least 1.5 wt. % based on the sum of components (B) and (C).
Dependencies are inferred from the claim text.