Solid Homogeneous Mixture Of Polyvinylacetate and Vinylacetate-Vinyl Laurate Copolymer Prepared By Sequential Solution Polymerization

Abstract

The invention provides a chewing gum base containing a homogeneous composition in solid form comprising a) from 50 to 90% by weight of polyvinyl acetate and b) from 10 to 50% by weight of vinyl acetate-vinyl laurate copolymer, the weight percentage based on the total weight of the composition.

1 . In a chewing gum comprising a chewing gum base composition and further additives, the improvement comprising incorporating, as at least part of the chewing gum base composition, a homogenous solid elastomer comprising:
 a) from 50 to 90 percent by weight of a polyvinyl acetate polymer, and   b) from 10 to 50 percent by weight of a vinyl acetate-vinyl laurate copolymer,   
       wherein the percents by weight are based on the total weight of the homogenous solid elastomer. 
     
     
         2 . The chewing gum of  claim 1 , wherein the chewing gum base composition comprises from 10 to 60 weight percent of the homogenous solid elastomer, based on the weight of the chewing gum base composition. 
     
     
         3 . The chewing gum of  claim 1 , wherein the chewing gum base composition consists of the homogenous solid elastomer. 
     
     
         4 . The chewing gum of  claim 11 , wherein the vinyl acetate-vinyl laurate copolymer contains 60-80 weight percent of vinyl acetate-derived moieties and 20-40 weight percent of vinyl laurate-derived moieties based on the weight of the vinyl acetate-vinyl laurate copolymer. 
     
     
         5 . The chewing gum of  claim 11 , wherein the homogenous solid elastomer is prepared by a process comprising solution polymerizing comonomers including vinyl acetate and vinyl laurate to form a vinyl acetate-vinyl laurate copolymer b), following which vinyl acetate monomer is added and polymerized after a monomer conversion of from 60 to 100% by weight of the comonomers used to form copolymer b), and isolating the product as a solid,
 wherein the homogenous solid elastomer comprises
 from 50-90% by weight, based on the total weight of the homogenous solid elastomer, of a) a polyvinyl acetate polymer containing more than 90% by weight of vinyl acetate derived moieties based on the weight of the polyvinyl acetate polymer, and 
 from 10 to 50% by weight based on the total weight of the homogenous solid elastomer, of b) a vinyl acetate-vinyl laurate copolymer containing 10-50% of vinyl laurate derived moieties based on the weight of the vinyl acetate-vinyl laurate copolymer. 
   
     
     
         6 . The chewing gum of  claim 1 , wherein the vinyl acetate polymer contains less than 10 weight percent of vinyl laurate-derived moieties, based on the weight of the vinyl acetate polymer. 
     
     
         7 . The chewing gum of  claim 1 , wherein the vinyl acetate polymer contains less than 5 weight percent of vinyl laurate-derived moieties, based on the weight of the vinyl acetate polymer. 
     
     
         8 . The chewing gum of  claim 1 , wherein the homogenous solid elastomer is prepared by separately preparing a vinyl acetate polymer and a vinyl acetate-vinyl laurate copolymer, and blending the vinyl acetate polymer and the vinyl acetate-vinyl laurate copolymer in the melt, and solidifying the melt. 
     
     
         9 . The chewing gum of  claim 1 , wherein the homogenous solid elastomer is prepared by dissolving a vinyl acetate-vinyl laurate copolymer in solvent, adding vinyl acetate monomer, polymerizing the vinyl acetate monomer, and removing solvent to form a homogenous solid elastomer. 
     
     
         10 . The chewing gum of  claim 1 , wherein the homogenous solid elastomer comprises from 65 to 75 weight percent vinyl acetate polymer and 35 to 25 weight percent vinyl acetate-vinyl laurate copolymer, based on the weight of the homogenous solid elastomer. 
     
     
         11 . The chewing gum of  claim 1 , wherein the weight-average molecular weight Mw of the polyvinyl acetate polymer a) is from 10,000 to 100,000 and the weight-average molecular weight Mw of the vinyl acetate-vinyl laurate copolymer b) is from 100,000 to 600,000.