US 11,654,098 B2
Process for preparing organopolysiloane gels
Frank Sandmeyer, Burgkirchen (DE); and Christoph Schosser, Burghausen (DE)
Assigned to WACKER CHEMIE AG, Munich (DE)
Appl. No. 16/622,056
Filed by WACKER CHEMIE AG, Munich (DE)
PCT Filed Jun. 12, 2017, PCT No. PCT/EP2017/064241
§ 371(c)(1), (2) Date Dec. 12, 2019,
PCT Pub. No. WO2018/228657, PCT Pub. Date Dec. 20, 2018.
Prior Publication US 2021/0145727 A1, May 20, 2021
Int. Cl. A61K 8/899 (2006.01); A61K 8/04 (2006.01); A61Q 19/00 (2006.01); A61K 8/895 (2006.01); C08G 77/50 (2006.01); C08G 77/08 (2006.01); A61K 8/891 (2006.01); C08G 77/00 (2006.01)
CPC A61K 8/899 (2013.01) [A61K 8/042 (2013.01); A61K 8/891 (2013.01); A61K 8/895 (2013.01); A61Q 19/00 (2013.01); C08G 77/08 (2013.01); C08G 77/50 (2013.01); A61K 2800/10 (2013.01); C08G 77/70 (2013.01)] 10 Claims
 
1. A process for producing organopolysiloxane gels, comprising:
reacting
(1a) unsaturated organopolysiloxane resins comprising units of the formulae
SiO2(Q units) and
R3SiO1/2 and R2R1SiO1/2(M units),
where
R each independently is a monovalent, optionally substituted hydrocarbon radical having 1 to 18 carbon atoms per radical,
R1 each independently is a monovalent hydrocarbon radical onto which Si-H groups are optionally added in a hydrosilylation reaction,
with the proviso that the organopolysiloxane resins contain at least 2 R1 radicals, and that the molar ratio of M units to Q units is in the range from 0.5 to 4.0, the organopolysiloxane resins optionally containing, in addition to the M and Q units, small amounts of RSiO3/2 (T) units and/or R2SiO2/2 (D) units, in amounts of 0.01 to 20 mol %, based on the sum total of all siloxane units, the organopolysiloxane resins optionally containing up to 10% by weight of Si-bonded hydroxyl or alkoxy groups,
and optionally
(1b) compounds having a polar organic group and a hydrosilylatable end group, with
(2) a mixture of two Si-H-containing organopolysiloxanes which have different average chain lengths, of the formula:
(R23-xHxSiO1/2) (R22SiO2/2)a(R2HSiO2/2)b(R23-xHxSiO1/2)  (I)
where R2 each independently is an unsubstituted or optionally heteroatom-substituted, aliphatic, cycloaliphatic or aromatic, optionally polycyclic, C1-C18 hydrocarbon radical,
x is 0 or 1,
a and b are each integers ≥0,
with the provisos that the sum total of a+b ≥30, that the organopolysiloxanes contain an average of at least 2 Si-bonded hydrogen atoms, and that the long-chain organopolysiloxane has at least 3 times the chain length (a+b) of the short-chain organopolysiloxane,
in the presence of
(3) catalysts that promote the addition of Si-bonded hydrogen onto aliphatic multiple bonds,
where (1a), optionally (1b) and (2) is/are dispersed in
(4) diluents
and the reaction is stopped by addition of
(5) stopper compounds used as catalyst poisons.