Curable silicone compositions comprising clustered functional polyorganosiloxanes and silicone reactive diluents

1. A curable silicone composition comprising a reaction product of a reaction of:

(I) a clustered functional polyorganosiloxane having at least one radical curable group selected from an acrylate group and a methacrylate group that comprises a reaction product of a reaction of:

a) a first polyorganosiloxane having an average, per molecule, of at least 2 aliphatically unsaturated organic groups,

b) a polyorganohydrogensiloxane having an average, per molecule, of 4 to 15 silicon atoms and at least 4 silicon bonded hydrogen atoms per aliphatically unsaturated organic group in component a),

c) a reactive species having, per molecule at least one aliphatically unsaturated organic group and one or more curable groups selected from acrylate groups and methacrylate groups,

in the presence of d) a first hydrosilylation catalyst and e) an isomer reducing agent;

(II) a silicone reactive diluent comprising a reaction product of a reaction of:

a) a siloxane compound according to the formula:

wherein:

each R is independently a monovalent hydrocarbon having 1 to 6 carbon atoms,

R′ is a monovalent hydrocarbon having 3 to 12 carbon atoms,

R″ is H or CH 3 , and

the subscripts m and n each independently have a value from 1 to 10, and

b) a second polyorganosiloxane having an average, per molecule, of at least 2 aliphatically unsaturated organic groups,

in the presence of c) a second hydrosilylation catalyst and d) an inhibitor for the second hydrosilylation catalyst; and

(III) a radical initiator.

2. The curable silicone composition as set forth in claim 1 , wherein the isomer reducing agent e) is present in an amount based on the total weight of the clustered functional polyorganosiloxane to produce at least a 10% reduction in the beta-addition of Si—H groups of the first polyorganosiloxane to the aliphatically unsaturated group of the reactive species as compared to a clustered functional polyorganosiloxane formed in the absence of the isomer reducing agent.

3. A method for forming a cured substrate, the method comprising: applying a curable silicone composition according to claim 1 to a substrate; and curing the curable silicone composition on the substrate to form the cured substrate.

4. A filled curable silicone composition comprising a filler and a curable silicone composition prepared by the process of claim 1 .

5. The filled curable silicone composition of claim 4 , where the filler comprises a thermally conductive filler.

6. The filled curable silicone composition of claim 4 , where the filled curable silicone composition further comprises one or more components selected from (IV) a moisture cure catalyst, (V) a crosslinker, (VI) a moisture cure resin and polymer, (VII) a solvent, (VIII) an adhesion promoter, (IX) a colorant, (X) a reactive diluent, (XI) a corrosion inhibitor, (XII) a polymerization inhibitor, (XIV) a filler treating agent, (XV) an acid acceptor, and a combination thereof.