Vinyl acetate-ethylene copolymer emulsion and paper coating composition based on the same

Abstract

The present invention relates to a vinyl acetate-ethylene copolymer emulsion and a paper coating composition based on the same. More specifically, the present invention relates to a vinyl acetate-ethylene copolymer emulsion based paper coating composition with low odor. The present invention also relates to processes for preparing the vinyl acetate-ethylene copolymer emulsion and the paper coating composition, and uses thereof.

1 . A low odor paper coating composition, comprising a solid component and a binder, characterized in that said binder comprises:
 (a) a vinyl acetate-ethylene copolymer-based emulsion, wherein the copolymer comprises, based on the total weight of the copolymer:
 (1) about 65-95 pphm of a moiety derived from vinyl acetate; 
 (2) about 5-35 pphm of a moiety derived from ethylene; and 
 (3) about 0-10 pphm of a moiety derived from other comonomers or functional monomers, 
   
       wherein the copolymer-based emulsion is formed by emulsion polymerization of the monomers in the presence of about 1-5 pphm of a surfactant and about 0-10 pphm of a polymeric protective colloid as emulsifier/protective colloid,
 (b) additional water. 
 
     
     
         2 . The paper coating composition according to  claim 1 , wherein the surfactant is selected from anionic surfactants, nonionic surfactants or combination thereof. 
     
     
         3 . The paper coating composition according to  claim 2 , wherein the anionic surfactants are selected from alkylsulfates, alkylsulfonates, alkyl benzenesulfonates, alkyl polyoxyethylene ether sulfates, alkylpolyoxyethylene-propylene ether sulfates, sodium fatty alcohol succinic acid mono ester sulfonates, disodium fatty alcohol polyoxyethylene ether sulfosuccinates, disodium fatty alcohol polyoxyethylene-propylene ether sulfosuccinates, alkylpolyoxyethylene phosphates, alkylpolyoxyethylene-propylene phosphates, alkali metal salts of fatty acids, or mixtures thereof. 
     
     
         4 . The paper coating composition according to  claim 2 , wherein the nonionic surfactants are selected from linear alkyl alcohol polyoxyethylene ethers, linear alkyl alcohol polyoxyethylene-propylene ethers, branched alkyl alcohol polyoxyethylene ethers, branched alkyl alcohol polyoxyethylene-propylene ethers, fatty acid polyoxyethylenemonoesters, fatty acid polyoxyethylene-propylenemonoesters, or mixtures thereof. 
     
     
         5 . The paper coating composition according to  claim 1 , wherein the polymeric protective colloid is selected from partially hydrolyzed polyvinyl alcohols, cellulose ethers, polyvinyl pyrrolidone, or mixtures thereof. 
     
     
         6 . The paper coating composition according to  claim 5 , wherein the polyvinyl alcohol has a degree of alcoholysis of about 75 to 95% and a degree of polymerization of about 200 to 4000. 
     
     
         7 . The paper coating composition according to  claim 1 , wherein other comonomers or functional monomers are selected from:
 vinyl esters of polyacid, wherein the specific monomer can include:   
       
         
           
           
               
               
           
         
       
       wherein each of R 1  and R 2  is hydrogen or alkyl provided that the total carbon atom number of R 1  and R 2  is from 1 to 14;
 acrylates, wherein the specific monomer can include: 
 
       
         
           
           
               
               
           
         
       
       wherein R 3  is hydrogen or alkyl group with 1 to 16 carbon atom(s);
 methacrylates, wherein the specific monomer can include: 
 
       
         
           
           
               
               
           
         
       
       wherein R is hydrogen or alkyl group with 1 to 16 carbon atom(s);
 maleate esters, wherein the specific monomer can include: 
 
       
         
           
           
               
               
           
         
       
       wherein each of R 5  and R 6  is alkyl group with 1 to 16 carbon atom(s);
 acrylic acid; methacrylic acid; maleic acid; maleic anhydride; fumaric acid; crotonic acid; itaconic acid; acrylonitrile; methylacrylonitrile; sodium vinylsulfonate; sodium vinyl benzenesulfonate; mono-sodium 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propylsulfonate; methacrylate ethyl trimethyl ammonium chloride; acrylamide; hydroxymethylacrylamide; hydroxyethylacrylamide; hydroxypropylacrylamide vinyltrimethoxysilane; vinyltriethoxysilane; vinyltri(2-methoxyethoxy)silane; methylacryloxypropyltrimethoxysilane; ethylene glycol acrylate; propylene glycol acrylate; glycidyl acrylate; diallyl maleate; diallyl phthalate; triallyl cyanurate; allyl methacrylate; ethylene glycol dimethylacrylate; pentaerythritol triacrylate; pentaerythritol tetraacrylate; ethyl acetoacetoxylmethylacrylate; diacetone acrylamide; allyl acrylamide; or mixtures thereof. 
 
     
     
         8 . The paper coating composition according to  claim 1 , wherein the solid component comprises kaolin, calcium carbonate or a mixture thereof. 
     
     
         9 . The paper coating composition according to  claim 1 , wherein the weight ratio of solid component to binder is bout 100:6 to 100:19, preferably about 100:8 to 100:16. 
     
     
         10 . A process for preparing the low odor paper coating composition according to  claim 1 , said process comprises
 (a) forming an ethylene-vinyl acetate copolymer-based emulsion by emulsion polymerizing a monomeric composition comprising:
 (1) about 65-95 pphm of a moiety derived from vinyl acetate; 
 (2) about 5-35 pphm of a moiety derived from ethylene; and 
 (3) about 0-10 pphm of a moiety derived from other comonomers or functional monomers, 
   
       in the presence of about 1-5 pphm, of a surfactant and about 0-10 pphm of a polymeric protective colloid as emulsifier/protective colloid;
 (b) mixing said ethylene-vinyl acetate copolymer-based emulsion with additional water to form a binder; 
 (c) mixing said binder with a solid component. 
 
     
     
         11 . A vinyl acetate-ethylene copolymer-based emulsion for low odor paper coating composition, wherein the copolymer comprises, based on the total weight of the copolymer:
 (1) about 65-95 pphm of a moiety derived from vinyl acetate;   (2) about 5-35 pphm of a moiety derived from ethylene; and   (3) about 0-10 pphm of a moiety derived from other comonomers or functional monomers,   
       wherein the copolymer-based emulsion is formed by emulsion polymerization of the monomers in the presence of about 1-5 pphm of a surfactant and about 0-10 pphm of a polymeric protective colloid as emulsifier/protective colloid. 
     
     
         12 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 , wherein the surfactant is selected from anionic surfactants, nonionic surfactants or combination thereof. 
     
     
         13 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 12 , wherein the anionic surfactants are selected from alkylsulfates, alkylsulfonates, alkyl benzenesulfonates, alkyl polyoxyethylene ether sulfates, alkylpolyoxyethylene-propylene ether sulfates, sodium fatty alcohol succinic acid mono ester sulfonates, disodium fatty alcohol polyoxyethylene ether sulfosuccinates, disodium fatty alcohol polyoxyethylene-propylene ether sulfosuccinates, alkylpolyoxyethylene phosphates, alkylpolyoxyethylene-propylene phosphates, alkali metal salts of fatty acids, or mixtures thereof. 
     
     
         14 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 12 , wherein the nonionic surfactants are selected from linear alkyl alcohol polyoxyethylene ethers, linear alkyl alcohol polyoxyethylene-propylene ethers, branched alkyl alcohol polyoxyethylene ethers, branched alkyl alcohol polyoxyethylene-propylene ethers, fatty acid polyoxyethylenemonoesters, fatty acid polyoxyethylene-propylenemonoesters, or mixtures thereof. 
     
     
         15 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 , wherein the polymeric protective colloid is selected from partially hydrolyzed polyvinyl alcohols, cellulose ethers, polyvinyl pyrrolidone, or mixtures thereof. 
     
     
         16 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 15 , wherein the polyvinyl alcohol has a degree of alcoholysis of about 75 to 95% and a degree of polymerization of about 200 to 4000. 
     
     
         17 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 , wherein other comonomers or functional monomers are selected from:
 vinyl esters of polyacid, wherein the specific monomer can include:   
       
         
           
           
               
               
           
         
       
       wherein each of R 1  and R 2  is hydrogen or alkyl group, provided that the total carbon atom number of R 1  and R 2  is from 1 to 14;
 acrylates, wherein the specific monomer can include: 
 
       
         
           
           
               
               
           
         
       
       wherein R 3  is hydrogen or alkyl group with 1 to 16 carbon atom(s); methacrylates, wherein the specific monomer can include: 
       
         
           
           
               
               
           
         
       
       wherein R is hydrogen or alkyl group with 1 to 16 carbon atom(s);
 maleate esters, wherein the specific monomer can include: 
 
       
         
           
           
               
               
           
         
       
       wherein each of R 5  and R 6  is alkyl group with 1 to 16 carbon atom(s);
 acrylic acid; methacrylic acid; maleic acid; maleic anhydride; fumaric acid; crotonic acid; itaconic acid; acrylonitrile; methylacrylonitrile; sodium vinylsulfonate; sodium vinyl benzenesulfonate; mono-sodium 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propylsulfonate; methacrylate ethyl trimethyl ammonium chloride; acrylamide; hydroxymethylacrylamide; hydroxyethylacrylamide; hydroxypropylacrylamide vinyltrimethoxysilane; vinyltriethoxysilane; vinyltri(2-methoxyethoxy)silane; methylacryloxypropyltrimethoxysilane; ethylene glycol acrylate; propylene glycol acrylate; glycidyl acrylate; diallyl maleate; diallyl phthalate; triallyl cyanurate; allyl methacrylate; ethylene glycol dimethylacrylate; pentaerythritol triacrylate; pentaerythritol tetraacrylate; ethyl acetoacetoxylmethylacrylate; diacetone acrylamide; allyl acrylamide; or mixtures thereof. 
 
     
     
         18 . The vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 , wherein the copolymer-based emulsion has a solid content of about 40 to 70% by weight based on the total weight of the emulsion. 
     
     
         19 . A process for preparing the vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 , said process comprises emulsion polymerizing a monomeric composition comprising:
 (1) about 65-95 pphm of a moiety derived from vinyl acetate;   (2) about 5-35 pphm of a moiety derived from ethylene; and   (3) about 0-10 pphm of a moiety derived from other comonomers or functional monomers,   
       in the presence of about 1-5 pphm of a surfactant and about 0-10 pphm of a polymeric protective colloid as emulsifier/protective colloid. 
     
     
         20 . The process according to  claim 19 , wherein the emulsion polymerization is carried out in the presence of a redox initiator. 
     
     
         21 . The process according to  claim 20 , wherein the initiator is selected from ammonium persulfate, sodium persulfate, hydrogen peroxide, tert-butyl peroxide, sodium formaldehyde-sulfoxylate, disodium 2-hydroxyl-2-sulfinatoacetate, ascorbic acid, erythorbic acid, alkali metal salts of ascorbic acid, alkali metal salts of erythorbic acid, sodium bisulfite, sodium sulfite, sodium metabisulfite, sodium thiosulfate, or mixtures thereof. 
     
     
         22 . A low odor paper coating composition comprising the vinyl acetate-ethylene copolymer-based emulsion according to  claim 11 . 
     
     
         23 . (canceled)