Heat conductive silicone rubber composition and molded article

A beat conductive silicone rubber composition comprising

• (A) 2 to 99 parts by weight of an organopolysiloxane containing, on the average, at least 0.1 silicon-bonded alkenyl radical in a molecule and having a viscosity of 50 to 100,000 mPa·s at 25° C.,
• (B) an organopolysiloxane containing, on the average, at least 2 silicon-bonded hydrogen atoms in a molecule and having a viscosity of 1 to 100,000 mPa·s at 25° C., in an amount to give 0.1 to 6.0 moles of silicon-bonded hydrogen atoms pa mole of total silicon-bonded alkenyl radicals in entire components,
• (C) a heat conductive filler in an amount of 100 to 3,500 parts by weight per 100 parts by weight of components (A) and (E) combined,
• (D) an effective amount of a platinum catalyst, and
• (E) 98 to 1 part by weight of an organopolysiloxane represented by the general formula (I) and having a molecular weight of at least 10,000, the amount of components (A) and (E) combined being 100 parts by weight,
• wherein R is each independently a substituted or unsubstituted, monovalent hydrocarbon radical, R1 is a monovalent hydrocarbon radical of 1 to 4 carbon atoms, R2 is an alkoxy, alkenyloxy or acyloxy radical of 1 to 4 carbon atoms, Z is an oxygen atom or a divalent hydrocarbon radical of 2 to 10 carbon atoms, r is 0, 1 or 2, k is an integer of 100 to 1,000, m is an integer of 0 to 20, n is an integer of 1 to 20, p is an integer of 50 to 1,000, q is an integer of 0 to 20, the sum of k+m+n is from 100 to 1,000, each of A1, A2 and A3 is R or -Z-Si(R1r)R2(3-r) wherein R1, R2, r and Z are as defined above, at least one -Z-Si(R1r)R2(3-r) radical being included per molecule.

A heat conductive silicone rubber composition comprising

• (A) 2 to 99 parts by weight of an organopolysiloxane containing, on the average, at least 0.1 silicon-bonded alkenyl radical in a molecule and having a viscosity of 50 to 100,000 mPa·s at 25° C.,
• (B) an organopolysiloxane containing, on the average, at least 2 silicon-bonded hydrogen atoms in a molecule and having a viscosity of 1 to 100,000 mPa·s at 25° C., in an amount to give 0.1 to 6.0 moles of silicon-bonded hydrogen atoms per mole of total silicon-bonded alkenyl radicals in entire components,
• (C) a heat conductive filler in an amount of 100 to 3,500 parts by weight per 100 parts by weight of components (A) and (E) combined,
• (D) an effective amount of a platinum catalyst, and
• (E) 98 to 1 part by weight of an organopolysiloxane represented by the general formula (I) and having a molecular weight of at least 10,000, the amount of components (A) and (E) combined being 100 parts by weight,
• wherein R is each independently a substituted or unsubstituted, monovalent hydrocarbon radical, R1 is a monovalent hydrocarbon radical of 1 to 4 carbon atoms, R2 is an alkoxy, alkenyloxy or acyloxy radical of 1 to 4 carbon atoms, Z is an oxygen atom or a divalent hydrocarbon radical of 2 to 10 carbon atoms, r is 0, 1 or 2, k is an integer of 100 to, 1,000, m is an integer of 0 to 20, n is an integer of 0 to 20, p is an integer of 50 to 899, q is an integer of 0 to 20, the sum of k+m+n is from 100 to 1,000, each of A1, A2 is -Z-Si(R1r)R2(3-r) and A3 is R or -Z-Si(R1r)R2(3-r) wherein R1, R2, r and Z are as defined above, and the number of silicon atoms participating in the siloxane (Si—O—Si) structure in the molecule is 130 to 1,000.