Patent ID: 11912871
Assignee: DOW GLOBAL TECHNOLOGIES LLC
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C | IPC C

Claim 13:
14. A process of preparing an aqueous dispersion comprising a silicone-acrylic polymer with a number average molecular weight of from 5,000 to 50,000 g/mol by free-radical polymerization, comprising: polymerization of a monomer mixture in an aqueous medium in the presence of an alkyl thiol containing a C6-C24 alkyl group or a substituted C6-C24 alkyl group;
wherein the monomer mixture comprises, based on the total weight of the monomer mixture,
(a) from 0.1% to 6.5% by weight of a (meth)acrylate functional siloxane having the structure of formula (I),, wherein R1 is hydrogen or a methyl group, R2, R3, R4, R5 and R6 are each independently selected from the group consisting of methyl, ethyl and benzyl groups, n is an integer in the range of from 0 to 20, p is an integer in the range of from 0 to 20, provided that n+p>5;
(b) from 0.1% to 4.5% by weight of an ionic monomer;
(c) from 30% to 75% by weight of a hard monomer; and
(d) from 20% to 65% by weight of a soft monomer;
wherein the silicone-acrylic polymer comprises residues of the alkyl thiol; and
wherein the weight ratio of structural units of the (meth)acrylate functional siloxane to residues of the alkyl thiol is less than 5.0.