摘要:
A method for forming a thermally conductive thermal radical cure silicone composition comprising (I) a clustered functional polyorganopolysiloxane; optionally (II) a silicone reactive diluent, (III) a filler comprising a thermally conductive filler, (III′) a filler treating agent, and (IV) a radical initiator is provided. In this method, the clustered functional polyorganosiloxane (I) and the optional silicone reactive diluent (II) are premade prior to their addition to respective components (III), (III′) and (IV).
摘要:
A hydrosilylation process is used to prepare a clustered functional polyorganosiloxane. The clustered functional polyorganosiloxane comprises a reaction product of a reaction of a) a polyorganosiloxane having an average, per molecule, of at least 2 aliphatically unsaturated organic groups; b) a polyorganohydrogensiloxane having an average of 4 to 15 silicon atoms per molecule; and c) a reactive species having, per molecule at least 1 aliphatically unsaturated organic group and 1 or more radical curable groups selected from an acrylate group and a methacrylate group; in the presence of d) a hydrosilylation catalyst, and e) an isomer reducing agent. The weight percent of silicon bonded hydrogen atoms in component b) divided by the weight percent of aliphatically unsaturated organic groups in component a) (the SiHb/Via ratio) ranges from 4/1 to 20/1. The resulting clustered functional polyorganosiloxane is useful in a curable silicone composition for electronics applications.
摘要:
An alkoxy-functional organopolysiloxane resin and polymer is disclosed that comprises the reaction product of a reaction of (i) an alkenyl-functional siloxane resin comprising R3SiO1/2 units and SiO4/2 units; (ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom at a molecular terminal; (iii) an endcapper according to the formula to the formula R23Si—(R22SiO)s—SiR22H or R23Si—(R22SiO)t—(HR2SiO)—SiR23, or combinations thereof; and (iv) a polyorganosiloxane having an average, per molecule, of at least 2 aliphatically unsaturated organic groups in the presence of a (v) hydrosilylation catalyst. In this alkoxy-functional organopolysiloxane resin and polymer, each R2 is independently a hydrocarbon radical and the subscripts s and t independently have values ranging from 0 to 10.
摘要:
A composition comprises (A) a silicone resin; (B) an organosilicon compound; (C) a hydrosilylation catalyst; and (D) a flame retardant component comprising aluminum hydroxide. The composition further comprises (E) a reflective component different from component (D) and comprising titanium dioxide. The composition forms articles having excellent physical properties, including reflectance, flame retardant properties, and self-extinguishing properties. An article formed from the composition and a method of forming a molded article are also provided.
摘要:
An inflatable vehicle safety device is provided that comprises an inflator, a fluid compartment, and a heat shield. The inflator is capable of providing an inflation fluid used to inflate the fluid compartment. The heat shield, which is located within the fluid compartment, comprises a fabric layer and a thermal barrier layer located adjacent to the film. The barrier layer includes at least one layer of silicone elastomer and one or more topcoats. The heat shield has a thermal resistance value of six seconds or more at 725°C when tested in a hot rod thermal resistivity test.
摘要:
A method comprises separate and consecutive steps (i) and (ii). Step (i) includes contacting a copper catalyst with hydrogen gas and a halogenated silane monomer at a temperature of 500 °C to 1400 °C to form a silicon-containing copper catalyst comprising at least 0.1 % (w/w) of silicon. Step (ii) includes contacting the silicon-containing copper catalyst with an organohalide at a temperature of 100°C to 600 °C to form a reaction product. The organohalide has formula H a C b X c , where X is a halogen atom, subscript a is an integer of 0 or more, subscript b is an integer of 1 or more, and subscript c is an integer of 2 or more. The method produces a reaction product. The reaction product includes a halogenated silahydrocarbylene.