Polymer dispersions and sound deadener compositions with emulsion polymer from two-stage preparation

Patent metadata

Field	Value
Publication number	US-9536513-B2
Application number	US-201414910607-A
Country	US
Kind code	B2
Filing date	Jul 25, 2014
Priority date	Aug 6, 2013
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A description is given of an aqueous polymer dispersion comprising a polymer which is obtainable by emulsion polymerization from a monomer mixture comprising as hydrophilic monomers ethoxylated (meth)acrylate monomer, acid monomer, and C1 to C20 hydroxyalkyl(meth)acrylate; and also at least one hydrophobic principal monomer, selected from C1 to C20 alkyl(meth)acrylates and vinylaromatics; and also, optionally, further monomers. This polymer is preparable by at least two-stage emulsion polymerization, where in a first polymerization stage the predominant fraction or the entire amount of the hydrophilic monomers is used, and in a later polymerization stage the predominant fraction or the entire amount of the hydrophobic monomers is used. The polymer dispersion is a suitable binder for aqueous particle dispersions, more particularly of sound deadener compositions, which comprise inorganic and optionally also organic particulate solids. Also described is a method for damping oscillations or vibrations of vehicle components.

First claim

The invention claimed is:

1. An aqueous polymer dispersion, comprising at least one polymer obtained by emulsion polymerization of a monomer mixture comprising hydrophilic monomers (a) to (c) having hydrophilic groups;
(a) at least one (meth)acrylate monomer comprising a polyethylene glycol group;
(b) at least one acid monomer; and
(c) at least one hydroxyalkyl(meth)acrylate having 1 to 20 C atoms in the alkyl group,

and also at least one hydrophobic principal monomer (d) selected from:
(d) an alkyl(meth)acrylate having 1 to 20 C atoms in the alkyl group, a vinylaromatic compound, and a mixture of these monomers,

and also, optionally:
(e) at least one further monomer, different from the monomers (a) to (d), which is ethylenically unsaturated and radically polymerizable,
wherein the polymer is obtained by an at least two-stage emulsion polymerization comprising a first polymerization stage with a predominant fraction or an entire amount of the hydrophilic monomers (a) to (c), and a later polymerization stage with a predominant fraction or an entire amount of the hydrophobic monomers (d).

2. The polymer dispersion according to claim 1 , wherein the polymer obtained by emulsion polymerization of a monomer mixture comprising
(a) at least 0.1 wt % of the at least one (meth)acrylate monomer with the polyethylene glycol group;
(b) at least 0.05 wt % of the at least one acid monomer;
(c) at least 0.05 wt % of the at least one hydroxyalkyl (meth)acrylate;
(d) at least 50 wt % of the at least one hydrophobic principal monomer (d);
(e) 0 to 10 wt % of the further monomer, different from the monomers (a) to (d), which are ethylenically unsaturated and radically polymerizable,
based in each case on the entire amount of monomers.

3. The polymer dispersion according to claim 1 , wherein the polymer is obtained by emulsion polymerization from a monomer mixture comprising
(a) at least one alkoxy-poly(ethylene glycol) (meth)acrylate;
(b) at least one selected from the group consisting of acrylic acid and methacrylic acid;
(c) at least one selected from hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, and hydroxybutyl(meth)acrylate;
(d) at least one hydrophobic monomer selected from an alkyl(meth)acrylate having from 1 to 10 C atoms in the alkyl group and styrene;
(e) optionally at least one further monomer, different from the monomers (a) to (d), which is ethylenically unsaturated and radically polymerizable, selected from the group consisting of a vinyl ester of a carboxylic acid comprising up to 20 C atoms, an ethylenically unsaturated nitrile, a vinyl halide, a vinyl ether of an alcohol comprising 1 to 10 C atoms, an aliphatic hydrocarbon having 2 to 8 C atoms and one or two double bonds and a mixture thereof.

4. The polymer dispersion according to claim 1 , wherein a glass transition temperature of the polymer ranges from −60° C. to less than or equal to +70° C.

5. The polymer dispersion according to claim 1 , wherein the first polymerization stage includes more than 50 wt % of the entire amount of the hydrophilic monomers (a) to (c) and at least 1 wt % of the entire amount of the hydrophobic monomers (d), and the later polymerization stage includes at least 80 wt % of the entire amount of the hydrophobic monomers (d).

6. An aqueous particle dispersion, comprising
(i) the aqueous polymer dispersion of claim 1 ; and
(ii) at least one inorganic filler; and
(iii) optionally at least one organic filler.

7. A sound deadener composition, comprising:
(a) 5 to 50 wt %, based on solids, of the aqueous polymer dispersion of claim 1 ;
(b) 40 to 80 wt % of at least one inorganic filler;
(c) 0 to 40 wt % of at least one organic filler;
(d) 10 to 40 wt % of water; and
(e) 0 to 10 wt % of at least one auxiliary.

8. The sound deadener composition of claim 7 , wherein the inorganic fillers are selected from kaolin, chalk, barium sulfate, carbon black, graphite, talc, clay minerals, microdolomite, finely ground quartz, and mica, the organic fillers are selected from powder coating materials, polymer powders of, for example, ground solid ethylene/vinyl acetate copolymer resins, dried acrylate dispersions, and polysaccharides, and the auxiliaries are used at not less than 0.1 wt % and are selected from thickeners, resins, plasticizers, dispersants, cosolvents, stabilizers, wetting agents, preservatives, foam inhibitors, glass beads or plastics beads, hollow glass or plastics bodies, antifreeze agents, antioxidants, UV absorbers, emulsifiers, siloxanes, organically modified siloxanes, and antistats.

9. A process for preparing the aqueous polymer dispersion of claim 1 , the process comprising conducting the first polymerization stage with at least the hydrophilic monomers (a) to (c), and conducting the later polymerization stage with at least the hydrophobic monomers (d).

10. A binder adapted for preparing an aqueous particle dispersion,
wherein:
the binder comprises the aqueous polymer dispersion of claim 1 ; and
the aqueous particle dispersion comprises dispersed inorganic particulate solids that are insoluble in water, and optionally organic particulate solids.

11. The binder of claim 10 , wherein the dispersed particulate solids are selected from inorganic fillers, more particularly from kaolin, chalk, barium sulfate, carbon black, graphite, talc, clay minerals, microdolomite, finely ground quartz, and mica.

12. The binder of claim 10 , wherein the aqueous particle dispersion is a sound deadener composition or a composition for underbody protection on a motor vehicle.

13. The sound deadener composition of claim 7 , which is adapted for vibration damping of bodywork parts of a vehicle.

14. A method for damping oscillations or vibrations of vehicle components, the method comprising applying the sound deadener composition of claim 7 to a vehicle component, and drying the sound deadener composition.

Assignees

• Basf Se

Inventors

• Wulff Dirk
• Dimmer Joerg-Alexander
• Preishuber-Pfluegl Peter

Classifications

• G10K11/162 Primary

  Selection of materials · CPC title

• C08F2/24

  with the aid of emulsifying agents · CPC title

• C09D133/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08K2003/3045

  Sulfates · CPC title

• C08F2/001 Primary

  Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer (C08F295/00, C08F297/00 take precedence) · CPC title