Patent ID: 7402647

Claim:
A process for preparing functionalized polyorganosiloxane (POS) resins comprising units M: (R 3 SiO 1/2 ), Q: (SiO 4/2 ) and M′: (Y a R 3-a SiO 1/2 ) and optionally D: (R 2 SiO 2/2 ) and/or D′: (RYSiO 2/2 ) and T: (RSiO 3/2 ) and/or T′: (YSiO 3/2 ), wherein: the radicals R, which are identical or different, represent C 1 -C 10 alkyl or C 8 -C 12 aryl; and the radicals Y, which are identical or different, represent a functional group Y selected from the group consisting of hydrogen, alkenyl, alkynyl, aryl, (alkyl)epoxy, ether, polyether, carboxylic acid, amide, amine, halide, alcohol, thiol and other sulfur derivative; said process comprising conducting a redistribution reaction between a POS resin and a POSf compound bearing functional units M′ and/or D′ and/or T′, as defined above, in the presence of an acid catalyst, wherein at least one catalyst has formula (I) below: (C m F 2m+1 SO 2 ) n A (I) wherein: m is an integer greater than or equal to 1; and n is an integer equal to 1 or 2 and A represents NH 2 or NH with: (i) n=1 and A=NH 2 or NHR with R being a radical of SO 2 -Z type with Z being a group other than C m F 2m+1 ; or (ii) n=2and A=NH; wherein the redistributed and functionalized resin obtained is subjected to at least one other redistribution/functionalization, using POSfs bearing functional units.