OXIME-FUNCTIONAL MOISTURE-CURABLE HOT MELT SILICONE PRESSURE-SENSITIVE ADHESIVES

摘要

OXIME-FUNCTIONAL MOISTURE-CURABLE HOT MELT SILICONE PRESSURE-SENSITIVE ADHESIVES A moisture-curable silicone hot-melt adhesive composition is disclosed, which composition comprises (i) a solid hydroxyl-functional organopolysiloxane resin comprising R3SiO1/2 siloxane units and SiO4/2 siloxane units in a molar ratio of 0.5/1 to 1.2/1, wherein R is selected from hydrocarbon or halogenated hydrocarbon radicals; (ii) a diorganopolysiloxane polymer having siliconbonded hydroxyl terminal groups and having a viscosity at 25.degree.C. of 100 to 500,000 mPa?s (centipoise), the weight ratio of said resin (i) to said polymer being (ii) in the range 40:60 to 75:25; (iii) a ketoximosilane, the amount of said ketoximosilane being sufficient to provide a molar ratio of X groups to total hydroxyl groups on said resin (i) and said diorganopolysiloxane (ii) of 0.9 to 3; and (iv) optionally, sufficient catalyst to accelerate the cure of said composition, said composition being an essentially solvent-free non-slump solid at room temperature, being extrudable at ?150.degree.C. and forming an essentially tackfree elastomer when cured.