Heat-conductive silicone grease composition

摘要

A heat-conductive silicone grease composition is provided comprising (A) a trialkoxysilyl-endcapped organopolysiloxane having a viscosity of 0.1-1,000 Pa·s at 25° C., (B) a specific organopolysiloxane, (C) a heat-conductive filler, and (D) a condensation catalyst. The composition is amenable to coat at the initial, thereafter increases its viscosity with moisture at room temperature rather than curing so that it remains flexible, easy to re-work, and anti-sagging, eliminates a need for cold storage and for hot application, avoids any undesired viscosity buildup, is easy to manufacture, and has good heat transfer.

主权项

1. A heat-conductive silicone grease composition that will increase its viscosity with moisture at room temperature, comprising
(A) 1 to 40 parts by weight of an organopolysiloxane capped with trialkoxysilyl at both ends and having a viscosity of 0.1 to 1,000 Pa·s at 25° C., (B) 60 to 99 parts by weight of an organopolysiloxane having the general formula (1):wherein R1 is each independently a substituted or unsubstituted monovalent hydrocarbon radical, R2 is each independently an alkyl, alkoxyalkyl, alkenyl or acyl radical, n is an integer of 5 to 100, and a is an integer of 1 to 3,
the sum of components (A) and (B) being 100 parts by weight, (C) 100 to 2,000 parts by weight of a heat-conductive filler having a heat conductivity of at least 10 W/m° C., and (D) 0.1 to 20 parts by weight of a condensation catalyst, wherein the viscosity of said composition as prepared is 50 to 250 Pa·s at 25° C. and wherein when said heat-conductive silicone grease composition increases its viscosity at a temperature of 23±2° C. and a relative humidity (RH) of 50±5% for 7 days, the viscosity corresponds to a hardness of 15 to 60 units as measured by an Asker hardness tester.