RTV silicone composition offering rapid bond strength

摘要

Disclosed is a curable two part sealant composition comprising a first component (A) and a second component (B), said first component (A) comprising: (a) diorganopolysiloxane in an amount ranging from 5 weight percent to 80 weight percent of the total composition wherein the silicon atom at each polymer chain end is silanol terminated; (b) diorganopolysiloxane in an amount ranging from 5 weight percent to 35 weight percent of the total composition wherein the silicon atom at each polymer chain end is alkyl terminated; said second component (B) comprising: (b) diorganopolysiloxane in an amount ranging from 5 weight percent to 35 weight percent of the total composition wherein the silicon atom at each polymer chain end is alkyl terminated; (c) an alkylsilicate in an amount ranging from 0.1 weight percent to about 10 weight percent of the total composition; (d) a condensation catalyst in an amount ranging from about 0.001 weight percent to 1 weight percent of the total composition; and (e) an alkoxysilane adhesion promoter in an amount ranging from 0.1 weight percent to 20 weight percent of the total composition; wherein the weight ratio of the first component (A) to second component (B) is approximately 13 to 1; and wherein said sealant composition has a green strength of from 6.895 kPa [1 psi] to517.1 kPa [75 psi] as measured by WPSTM test C-1221 after curing for a time period of from 1 minute to 60 minutes.