초록 ▼

The combination of (1) a polyorganosiloxane composition curable by a platinum catalyzed hydrosilation reaction with (2) up to about 20 percent, based on the weight of (1), of a polyorganosiloxane composition comprising the mixture of a liquid hydroxyl-terminated polydiorganosiloxane and a moisture r

The combination of (1) a polyorganosiloxane composition curable by a platinum catalyzed hydrosilation reaction with (2) up to about 20 percent, based on the weight of (1), of a polyorganosiloxane composition comprising the mixture of a liquid hydroxyl-terminated polydiorganosiloxane and a moisture reactive organosilicon crosslinking agent, or the reaction product of said mixture, and an organotitanate catalyst yields elastomers that cure rapidly at temperatures of at least about 80 degrees C. and cohesively bond to inorganic substrates such as glass and metal. The resultant cured elastomer exhibits a durometer or less than about 20 on the Shore A durometer scale.

대표청구항 ▼

A curable, self adhering polyorganosiloxane composition comprising the product obtained by blending to homogeneiety A. a first organosiloxane material which is curable by a platinum-catalyzed hydrosilation reaction and comprises (1) a liquid polydiorganosiloxane containing two vinyl radicals per mol

A curable, self adhering polyorganosiloxane composition comprising the product obtained by blending to homogeneiety A. a first organosiloxane material which is curable by a platinum-catalyzed hydrosilation reaction and comprises (1) a liquid polydiorganosiloxane containing two vinyl radicals per molecule, (2) an organohydrogensiloxane containing at least three silicon bonded hydrogen atoms per molecule in an amount sufficient to cure the vinyl containing materials present in said composition; and (3) a platinum containing catalyst in an amount sufficient to promote curing of said vinyl containing materials: B. from 0 to 60 percent by weight, based on the weight of said first organosiloxane composition, of a benzene-soluble copolymer, consisting essentially of units of the general formula SiO2, in addition to triorganosiloxy units of the general formula R33SiO½and diorganovinylsiloxy units of the general formula CH2〓CH(R4)2SiO½, where the molar ratio of the combination of diorganovinylsiloxy and triorganosiloxy units to SiO4/2 units is from 0.7:1 to 1.2:1, inclusive, and the diorganovinylsiloxy units constitute from 2 to 8 percent by weight of said copolymer; C. from 0.1 to 20 percent by weight, based on the weight of said first organosiloxane material, of a moisture curable organosiloxane material that is compatible with said first organosiloxane material and comprises (1) a mixture of a liquid hydroxyl terminated polydiorganosiloxane and a crosslinking agent consisting essentially of a silane wherein the silicon atom is bonded to at least three alkoxy groups or a reaction product of said mixture, where there is present at least 0.5 mole of silane per mole of silicon-bonded hydroxyl groups in the polydiorganosiloxane: and (2) an amount sufficient to promote curing of said moisture curable organosiloxane material of a titanium orthoester catalyst, where the elastomer obtained by curing said composition exhibits a durometer of no greater than 20 on the Shore A durometer scale.