Bimorphological latex

Patent metadata

Field	Value
Publication number	US-9920194-B2
Application number	US-201615075244-A
Country	US
Kind code	B2
Filing date	Mar 21, 2016
Priority date	Mar 24, 2015
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

The present invention relates to a composition comprising a bimorphological aqueous dispersion of first and second polymer particles, wherein the first polymer particles comprise a shell and a phosphorus acid functionalized protuberating core, and the second polymer particles do not comprise a protuberating core. The composition is useful for pigmented coatings formulations.

First claim

The invention claimed is:

1. A composition comprising an aqueous dispersion of first and second acrylic-based polymer particles, wherein the first polymer particles each comprise a shell with a protuberating phosphorus acid functionalized core, and wherein none of the second polymer particles comprise a protuberating core; wherein the weight-to-weight ratio of the polymer particles with a protuberating core to the polymer particles without a protuberating core is in the range of 25:75 to 75:25; wherein the volume average particle size of the polymer particles with the protuberating core is in the range of from 110 nm to 160 nm; and the volume average particle size of the particles without a protuberating core is in the range of from 70 nm to 140 nm; wherein the composition of the shells of the first polymer particles is substantially identical to the composition of the second polymer particles; and wherein the ratio of volume average particle size of the particles with a protuberating core to the particles without a protuberating core is from 1.45:1 to 0.9:1.

2. The composition of claim 1 wherein the protuberating core of the first polymer particles comprises structural units of a) methyl methacrylate or styrene or a combination thereof; b) one or more acrylate monomers selected from the group consisting of ethyl acrylate, butyl acrylate, 2-propylheptyl acrylate, and 2-ethylhexyl acrylate; and c) phosphoethyl methacrylate; and wherein the shells of the first polymer particles and the second polymer particles each comprise structural units of a) methyl methacrylate or styrene or a combination thereof; and b) one or more acrylate monomers selected from the group consisting of ethyl acrylate, butyl acrylate, 2-propylheptyl acrylate, and 2-ethylhexyl acrylate; based on the weight of the second seed polymer particles; wherein the ratio of the volume average particle size of the particles with a protuberating core to the particles without a protuberating core is from 1.42:1 to 1:1; and wherein the shells of the first polymer particles and the second polymer particles comprise a substantial absence of structural units of a phosphorus acid monomer.

3. The composition of claim 2 wherein the protuberating core further comprises: d) structural units of a carboxylic acid monomer or a salt thereof; and e) structural units of a multiethylenically unsaturated monomer; and wherein the shells of the first polymer particles and the second polymer particles further comprise: d) structural units of a carboxylic acid monomer or a sulfur acid monomer or a salt thereof or a combination thereof; and e) less than 0.5 weight percent structural units of a phosphorus acid monomer; wherein the weight-to-weight ratio of the polymer particles with the protuberating core to the polymer particles without the protuberating core is in the range of 50:50 to 68:32.

4. The composition of claim 3 wherein the protuberating core comprises, based on the weight of the core, a) 3 to 8 weight percent structural units of phosphoethyl methacrylate or a salt thereof; b) from 1 to 5 weight percent structural units of acrylic acid or methacrylic acid or a salt thereof; c) from 0.2 to 5 weight percent structural units of a multiethylenically unsaturated monomer; d) from 50 to 65 weight percent structural units of butyl acrylate; and e) 25 to 45 weight percent structural units of methyl methacrylate; and wherein the first polymer particle shells and the second polymer particles each comprise, based respectively on the weight of the first polymer particle shells and the second polymer particles: a) from 40 to 60 weight percent structural units of butyl acrylate or 2-ethylhexyl acrylate or a combination thereof; b) from 40 to 60 weight percent structural units of methyl methacrylate or styrene or a combination thereof; c) from 0.1 to 5 weight percent structural units of acrylic acid or methacrylic acid or sodium 4-vinylbenzenesulfonate or 2-acrylamido-2-methyl propanesulfonic acid or a salt thereof or a combination thereof; and d) 0 weight percent structural units of a phosphorus acid monomer.

5. The composition of claim 4 wherein the volume average particle size of the polymer particles with a protuberating core is in the range of from 120 nm to 150 nm; and the volume average particle size of the particles without a protuberating core is in the range of from 80 to 130 nm; and wherein the ratio of the volume average particle size of the protuberating core particles to the non-protuberating core particles is from 1.42:1 to 1.2:1.

6. The composition of claim 1 which further includes TiO 2 particles, wherein at least a portion of the first polymer particles adsorb to the TiO 2 particles to form composite particles.

7. The composition of claim 6 which further comprises one or more of components selected from the group consisting of defoamers, surfactants, dispersants, rheology modifiers, and neutralizing agents.

Assignees

• Rohm & Haas

Inventors

• Bohling James C
• Brownell Arnold S
• Gao Wei
• Killian Ericka Lynn
• Tiwary Yogesh

Classifications

• C08L2205/08

  containing additives to improve the compatibility between two polymers · CPC title

• C08L33/08 Primary

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08L2207/53

  Core-shell polymer · CPC title

• C08F220/06

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• C08L2205/02

  containing two or more polymers of the same C08L -group · CPC title