| 主权项 |
1. A multiphase emulsion polymer for coating compositions, said multiphase emulsion polymer comprising at least one hard phase polymer having a glass transition temperature of from 0 to 100° C. and at least one soft phase polymer having a glass transition temperature of less than 0° C. and at least 20 to 100° C. lower than the glass transition temperature of the hard phase polymer, wherein the hard phase polymer is a copolymer of one or more ethylenically unsaturated monomer, and one or more oxyalkylene-containing (meth)acrylate corresponding to formula (I) or (II) or a mixture thereof:
CH2═C(R1)—C(═O)—O—[X—O]n—R2; (I) CH2═C(R1)—C(═O)—O—[X—O]n—P(═O)(OY)2; (II) wherein R1 is or CH3, R2 is H or a C1-C8 alkyl group, each X is independently —(CH2)2—, —CH2CH(CH3)— or —CH(CH3)CH2—, each Y is independently H, ammonium or an alkali metal atom, and n is an integer of from 1 to 30, wherein the soft phase polymer is a copolymer of monomers selected from the group consisting of C1-C18 alkyl(meth)acrylates, halo- and hydroxyl substituted alkyl esters of (meth)acrylic acid, vinyl esters of linear and branched caboxylic acids, having 2 to 20 carbon atoms, unsaturated C3-C6 monocarboxylic acid, monoesters of unsaturated C4-C6 dicarboxylic acids, unsaturated C4-C6 dicarboxylic acids, (meth)acrylonitrile, cycloalkyl(meth)acrylates, aryl and alkaryl esters of (meth)acrylates, acetoacetate-containing acrylate monomers, olefins, dienes, wherein the at least one hard polymer phase is formed as a first stage polymer and the at least one soft polymer phase is subsequently polymerized in the presence of the first stage polymer, and wherein the multiphase emulsion polymer is in the form of latex particles and wherein the latex particles comprise an inner phase comprised of the soft phase polymer and an outer phase comprised of the hard phase polymer. |
