| abstract |
Film-forming barrier polymer, which has the dry-based composition: a) from 45 to 90% by weight of a starch and / or a modified starch selected from modified starches by reaction with a hydroxyalkyl group, an acetate or a dicarboxylic acid anhydride or graft polymer; b) from 4 to 12% by weight of a water-soluble polymer selected from polyvinyl alcohol, polyvinyl acetate and copolymers of ethylene and vinyl alcohol having a melting point compatible with the molten state of starch components; c) from 5 to 45% by weight of a non-crystallizable mixture of sorbitol and at least one other plasticizer selected from glycerol, maltitol, xylitol, mannitol, glycerol trioleate, soybean oil or epoxidized flaxseed, tributyl citrate, citrate acetyltriethyl, glyceryl triacetate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate; poly (ethylene oxide) or polyethylene glycol; d) from 0.3 to 2.5% by weight of a salt or C12-22 fatty acid; e) from 0.25% to 3% of an emulsifying system having a lipophilic-hydrophilic equilibrium value of between 2 and 10. |