Pigment dispersant, method of making coating compositions, and coating compositions

Abstract

A coating composition comprises at least one pigment dispersed in an acrylic polymer, wherein the acrylic polymer is polymerized from a mixture of ethylenically unsaturated monomers comprising: (a) one or more monomers having active hydrogen functionality; (b) at least about 5% by weight of one or more monomers selected from the group consisting of monomers having a carboxylic acid group in which the carbonyl carbon is separated from the closest ethylenically unsaturated carbon by at least four atoms, ω-methyloxy-polyoxyethylene(meth)acrylates, ω-methyloxy-poly(oxyethylene-co-oxypropylene)(meth)acrylates, and combinations thereof; (c) optionally hydroxyethylene ethyl urea (meth)acrylate; and (d) up to about 50 percent by weight of one or more monomers selected from the group consisting of aromatic polymerizable monomers, wherein the monomers (b) and (c) combined are from about 5 to about 45 percent by weight of the mixture of ethylenically unsaturated monomers.

1 . A coating composition comprising at least one pigment dispersed in an acrylic polymer, wherein the acrylic polymer is polymerized from a mixture of ethylenically unsaturated monomers comprising: 
 (a) one or more monomers having active hydrogen functionality;    (b) at least about 5% by weight of one or more monomers selected from the group consisting of monomers having a carboxylic acid group in which the carbonyl carbon is separated from the closest ethylenically unsaturated carbon by at least four atoms, ω-methyloxy-polyoxyethylene (meth)acrylates, ω-methyloxy-poly(oxyethylene-co-oxypropylene) (meth)acrylates, and combinations thereof;    (c) optionally hydroxyethylene ethyl urea (meth)acrylate; and    (d) up to about 50 percent by weight of one or more monomers selected from the group consisting of aromatic polymerizable monomers,    wherein the monomers (b) and (c) combined are from about 5 to about 45 percent by weight of the mixture of ethylenically unsaturated monomers.    
   
   
       2 . A coating composition according to  claim 1 , wherein monomer (a) is selected from the group consisting of acrylamide, methacrylamide, beta-hydroxycarbamate acrylate, beta-hydroxycarbamate methacrylate, hydroxyalkyl(meth)acrylates, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, hydroxybutyl(meth)acrylate, esters of epsilon caprolactone and hydroxyalkyl(meth)acrylates, mono(meth)acrylates of polyethylene glycols, and combinations thereof.  
   
   
       3 . A coating composition according to  claim 1 , wherein the acrylic polymer has a weight average molecular weight of from about 8,000 to about 70,000.  
   
   
       4 . A coating composition according to  claim 1 , wherein the acrylic polymer has a carboxylic acid equivalent weight of from about 800 to about 2000.  
   
   
       5 . A coating composition according to  claim 1 , wherein the acrylic polymer has an active hydrogen group equivalent weight of from about 400 to about 2000.  
   
   
       6 . A coating composition according to  claim 1 , wherein monomer (b) comprises a β-carboxyethyl acrylate.  
   
   
       7 . A coating composition according to  claim 1 , wherein monomer (b) comprises an ω-methyloxy-polyoxyethylene (meth)acrylate.  
   
   
       8 . A coating composition according to  claim 1 , wherein the mixture of ethylenically unsaturated monomers comprises from about 1 to about 10 weight percent of hydroxyethylene ethyl urea (meth)acrylate.  
   
   
       9 . A coating composition according to  claim 1 , wherein the mixture of ethylenically unsaturated monomers comprises from about 5 to about 50 weight percent of styrene.  
   
   
       10 . A coating composition according to  claim 1 , wherein the coating composition is a solventborne coating composition.  
   
   
       11 . A waterborne basecoat composition, comprising an aqueous dispersion having at least one pigment dispersed by an acrylic polymer, wherein the acrylic polymer is polymerized from a mixture of ethylenically unsaturated monomers comprising: 
 (a) one or more monomers having active hydrogen functionality;    (b) at least about 5% by weight of one or more monomers selected from the group consisting of monomers having a carboxylic acid group in which the carbonyl carbon is separated from the closest ethylenically unsaturated carbon by at least four atoms, ω-methyloxy-polyoxyethylene (meth)acrylates, and combinations thereof;    (c) optionally hydroxyethylene ethyl urea (meth)acrylate; and    (d) up to about 50 percent by weight of one or more monomers selected from the group consisting of aromatic polymerizable monomers,    wherein the monomers (b) and (c) combined are from about 5 to about 45 percent by weight of the mixture of ethylenically unsaturated monomers.    
   
   
       12 . A waterborne basecoat composition according to  claim 11 , further comprising a film-forming polymer other than the acrylic polymer dispersing the pigment.  
   
   
       13 . A waterborne basecoat composition according to  claim 12 , further comprising a crosslinking agent.  
   
   
       14 . A waterborne basecoat composition according to  claim 12 , wherein monomer (a) is selected from the group consisting of acrylamide, methacrylamide, beta-hydroxycarbamate acrylate, beta-hydroxycarbamate methacrylate, hydroxyalkyl(meth)acrylates, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, hydroxybutyl (meth)acrylate, esters of epsilon caprolactone and hydroxyalkyl(meth)acrylates, mono(meth)acrylates of polyethylene glycols, and combinations thereof.  
   
   
       15 . A waterborne basecoat composition according to  claim 12 , wherein the acrylic polymer has a weight average molecular weight of from about 8,000 to about 70,000.  
   
   
       16 . A waterborne basecoat composition according to  claim 12 , wherein the acrylic polymer has a carboxylic acid equivalent weight of from about 800 to about 2000.  
   
   
       17 . A waterborne basecoat composition according to  claim 12 , wherein the acrylic polymer has an active hydrogen group equivalent weight of from about 400 to about 2000.  
   
   
       18 . A waterborne basecoat composition according to  claim 12 , wherein monomer (b) comprises a β-carboxyethyl acrylate.  
   
   
       19 . A waterborne basecoat composition according to  claim 12 , wherein monomer (b) comprises an ω-methyloxy-polyoxyethylene (meth)acrylate.  
   
   
       20 . A waterborne basecoat composition according to  claim 12 , wherein the mixture of ethylenically unsaturated monomers comprises from about 1 to about 10 weight percent of hydroxyethylene ethyl urea (meth)acrylate.  
   
   
       21 . A waterborne basecoat composition according to  claim 12 , wherein the mixture of ethylenically unsaturated monomers comprises from about 5 to about 50 weight percent of styrene.