| 摘要 |
<p>A silicone adhesive composition comprises a mixture of: (A) 40-95 parts of an alkenyl functional siloxane resin consisting of 0.5-1.5 R3SiO1/2 siloxane units per SiO4/2 siloxane unit, contg. 0.01-22 wt.% alkenyl functionality; (B) 0.5-20 parts of a SiH containing polyorganosiloxane having an average of 1.7 or more silicon-bonded hydrogen atoms per molecule and having a viscosity of 0.8-2,000 mm2/s; (C) a siloxane represented by monomers of formula R14-ySi(OR2)y or an oligomeric reaction products of partial hydrolysis and condensation of them; (D) a hydrosilation catalyst in amount to promote curing of the composition; and (E) a moisture curing catalyst to promote the moisture initiated curing of the alkoxy radicals. One or more of the resin (A), or the SiH containing polyorganosiloxane (B) contain a curing radical of the formula-ZSiR1x(OR2)3-x. The adhesive composition has a viscosity of 5-1,500 Pa's at 25 [deg]C in the absence of solvent. The composition first cures to a composition having green strength and a movable bond and then further cures to a composition having an immovable bond. In the formulae, R= 1-6C monovalent hydrocarbon or -ZSiR1x(OR2)3-x, with the provision that one or more is alkenyl; R1 = 1-6C alkyl or 6-10C aryl; R2 = 1-3C alkyl and alkoxyalkyl; y = 2-4; Z = divalent linking radical; and x = 0 or 1.</p> |
