Sulfopolyester polymer compositions with improved water dispersibility

Abstract

A coating composition containing (A) a sulfopolyester, (B) water, and (C) a polymer resin. The sulfopolyester comprises residues of (a) an acid component comprising (i) a dicarboxylic acid compound, a derivative of a dicarboxylic acid compound, or combinations thereof and (ii) a sulfomonomer having at least one ionic sulfonate group covalently bonded directly or indirectly to an aromatic or cycloaliphatic ring and (b) a polyhydroxyl component comprising a 2,2,4,4-tetralkylcyclobutane-1,3-diol. The polyhydroxyl component may further contain residues of 1,4-cyclohexanedimethanol, neopentyl glycol, or a mixture thereof.

What we claim is: 
     
         1 . A coating composition comprising:
 A. a sulfopolyester present in an amount of 5 to 95 weight %, based on the weight of the total resin solids of (A) and (C), said sulfopolyester containing residues of 2,2,4,4-tetraalkylcyclobutanediol (TACD);   B. water present in an amount of 50 to 85 weight %, based on the weight of the coating composition; and   C. a polymer resin present in an amount of 5 wt % to 95 wt %, based on the weight of the total resin solids of (A) and (C).   
     
     
         2 . The coating composition of  claim 1 , wherein the TACD comprises 2,2,4,4-tetramethylcyclobutane-1,3-diol. 
     
     
         3 . The coating composition of  claim 1 , wherein the sulfopolyester comprises the residues of:
 (i) a polyhydroxyl component comprising:
 a. TACD in an amount ranging from 10 mole % to 60 mole %, based on the moles of the polyhydroxyl component, and 
 b. a second polyhydroxyl compound comprising neopentyl glycol, 1,4-cyclohexanedimethanol (CHDM), or a mixture thereof, in a cumulative amount ranging from 40 mole % to 90 mole %, based on the moles of the polyhydroxyl component; and 
   (ii) an acid component comprising:
 a. isophthalic acid, dimethyl isophthalate, terephthalic acid, dimethyl terephthalate, or a mixture thereof, in a cumulative amount from 85 mole % to 95 mole %, based on the moles of the acid component, and 
 b. a sulfomonomer having at least one ionic sulfonate group covalently bonded directly or indirectly to an aromatic or cycloaliphatic ring in an amount ranging from 5 mole % to 15 mole %, based on the moles of the acid component, 
   wherein the total mole % of the polyhydroxyl component is 100 mole %, and the total mole % of the acid component is 100 mole %.   
     
     
         4 . The coating composition of  claim 1 , wherein the sulfopolyester further comprises the residues of a branching monomer having 3 or more functional groups selected from hydroxyl, carboxyl, and combinations thereof in an amount ranging from greater than 0 to 25 mole %, based on the total moles of all monomers. 
     
     
         5 . The coating composition of  claim 4 , wherein the branching monomer comprises 1,1,1-trimethylol propane, 1,1,1-trimethylolethane, glycerin, pentaerythritol, erythritol, threitol, dipentaerythritol, sorbitol, trimellitic anhydride, pyromellitic dianhydride, dimethylol propionic acid, or combinations thereof. 
     
     
         6 . The coating composition of  claim 1 , which comprises 5 to 50 wt % of the sulfopolyester and 50 to 95 wt % of the polymer resin. 
     
     
         7 . The coating composition of  claim 1 , which comprises 5 to 35 wt % of the sulfopolyester and 65 to 95 wt % of the polymer resin. 
     
     
         8 . The coating composition of  claim 1 , wherein the polymer resin comprises polyester, polyester-amid, polyamide, polyurethane, or polyisocyanate. 
     
     
         9 . The coating composition of  claim 1 , wherein the sulfomonomer comprises 5-sodiosulfoisophthalic acid or dimethyl 5-sodiosulfoisophthalate.