Patent ID: 7432338
Filing Date: 2008-10-07
Classification: C07F,C08G,C08L

Abstract:
1. A method comprising (1) heating in the presence of an acidic cyclosiloxane ring opening polymerization catalyst, a mixture comprising (i) at least one organohydrogensilicon compound containing at least one silicon-bonded hydrogen atom per molecule or a reaction product obtained by mixing in the presence of a platinum group metal-containing catalyst at least one organohydrogensilicon compound containing at least one silicon-bonded hydrogen atom per molecule and at least one compound having at least one aliphatic unsaturation where in each case the organohydrogensilicon compound is described by formula (I) where each R is independently selected from a hydrogen atom and a monovalent hydrocarbon group comprising 1 to 20 carbon atoms which is free from aliphatic unsaturation, a is an integer from 1 to 18, b is an integer from 1 to 19, a+b is an integer from 3 to 20, each X is an independently selected functional group selected from a halogen atom, an ether group, an alkoxy group, an alkoxyether group, an acyl group, a silyl group, or a —Z—R 4 group, where each Z is independently selected from an oxygen and a divalent hydrocarbon group comprising 2 to 20 carbon atoms, each R 4 group is independently selected from —BR u Y 2−u , —SiR v Y 3−v , or a group described by formula (II): where B refers to boron, each R is as described above, the sum of c+d+e+f+g+h+i+j is at least 2, n is an integer from 0 to 3, o is an integer from 0 to 2, p is an integer from 0 to 1, q is an integer from 0 to 1, r is an integer from 0 to 2, s is an integer from 0 to 2, t is an integer from 0 to 3, u is an integer from 0 to 2, v is an integer from 0 to 3, each Y is an independently selected functional group selected from a halogen atom, an ether group, an alkoxy group, an alkoxyetber group, an acyl group, a silyl group, or a Z-G group, where Z is as described above, each G is a cyclosiloxane described by formula (III): where R and X are as described above, k is an integer from 0 to 18, m is an integer from 0 to 18, k+m is an integer from 2 to 20, provided in formula (II) that one of the Y groups is replaced by the Z group bonding the R 4 group to the cyclosiloxane of formula (I), and provided further at least one X group of Formula (I) is a —Z—R 4 group; (ii) at least one endblocker described by formula (IV) R′ (iii) at least one organosiloxane chosen from a hydrolyzate described by formula (V) HO(MeR′SiO) provided if component (i) is a reaction product and it does not contain any silicon-bonded hydrogen bonds then at least one R′ of either component (ii) or (iii) is hydrogen, so to cause polymerization of components (i), (ii), and optionally (iii) to form silicon-bonded hydrogen containing branched polymers.