Abstract: A process for producing vinyl acetate polymers comprises, after polymerization of at least one monomer comprising vinyl acetate, adding a conjugated polyene having a boiling point of at least 20° C. Saponified products of the vinyl acetate polymers obtained by this process can give molded articles causing little coloring and generation of gel-like agglomerates.

Abstract: A process for producing vinyl acetate polymers comprises, after polymerization of at least one monomer comprising vinyl acetate, adding a conjugated polyene having a boiling point of at least 20.degree. C. Saponified products of the vinyl acetate polymers obtained by this process can give molded articles causing little coloring and generation of gel-like agglomerates.

Abstract: Process for producing ethylene-vinyl ester copolymers using a polymerization solvent of a dialkyl sulfoxide (process X); process for producing ethylene-vinyl alcohol copolymer by liquid phase saponification using a solvent of a dialkyl sulfoxide (process Y); and process for producing shaped articles which comprises contacting the ethylene-vinyl alcohol copolymer obtained by the process Y, or that obtained by saponifying the ethylene-vinyl ester copolymer obtained by process X, to a non-solvent for ethylene-vinyl alcohol copolymer.Ethylene-vinyl ester copolymers having a wide range of ethylene content and higher degree of polymerization than that with solution polymerization using methanol.The rate of saponification is higher than that with single solvent system of lower alcohol.Production cost is low, because production process of polymer is directly connected to that of shaped articles utilizing the polymer.

Abstract: Provided are compositions comprising a saponified product of an ethylene-vinyl acetate copolymer having an ethylene content of 20 to 80 mol % and a saponification degree of vinyl acetate component of at least 95 mol %, said composition containing 20 to 200 ppm as converted to alkali metal of an alkali metal acetate, 30 to 250 ppm of acetic acid, and 5 to 500 ppm as converted to phosphate ion of phosphoric acid or an alkali metal hydrogenphosphate, and having a content ratio of acetic acid/alkali metal acetate of 0.1 to 1 and the flow characteristic that the extrusion rate does not substantially increase for at least 10 hours in the relationship between the heating time and the extrusion rate with a capillary rheometer (Koka Flow Tester) at at least one temperature 10.degree. to 80.degree. C. above the melting point.

Abstract: An aqueous dispersion comprising a dispersoid of an ethylene-vinyl alcohol copolymer having an ethylene content of 15 to 65 mole % and a dispersion stabilizer of a saponified product of an ethylene-vinyl ester copolymer having an ionic group and having an ethylene content of 10 to 70 mole % and a saponification degree of at least 80%. According to the present invention, aqueous dispersions with high solid concentration and having excellent stability during storage or upon use. The film obtained by applying and then drying the aqueous dispersion has excellent gas barrier properties.

Abstract: An aqueous dispersion comprising a dispersoid of an ethylene-vinyl alcohol copolymer having an ethylene content of 15 to 65 mole % and a dispersion stabilizer of a saponified product of an ethylene-vinyl ester copolymer having an ionic group and having an ethylene content of 10 to 70 mole % and a saponification degree of at least 80%. According to the present invention, aqueous dispersions with high solid concentration and having excellent stability during storage or upon use. The film obtained by applying and then drying the aqueous dispersion has excellent gas barrier properties.

Abstract: Process for producing ethylene-vinyl ester copolymers using a polymerization solvent of a dialkyl sulfoxide (process X); process for producing ethylene-vinyl alcohol copolymer by liquid phase saponification using a solvent of a dialkyl sulfoxide (process Y); and process for producing shaped articles which comprises contacting the ethylene-vinyl alcohol copolymer obtained by the process Y, or that obtained by saponifying the ethylene-vinyl ester copolymer obtained by process X, to a non-solvent for ethylene-vinyl alcohol copolymer.Ethylene-vinyl ester copolymers having a wide range of ethylene content and higher degree of polymerization than that with solution polymerization using methanol.The rate of saponification is higher than that with single solvent system of lower alcohol.Production cost is low, because production process of polymer is directly connected to that of shaped articles utilizing the polymer.

Abstract: Provided are compositions comprising a saponified product of an ethylene-vinyl acetate copolymer having an ethylene content of 20 to 80 mol % and a saponification degree of vinyl acetate component of at least 95 mol %, said composition containing 20 to 200 ppm as converted to alkali metal of an alkali metal acetate, 30 to 250 ppm of acetic acid, and 5 to 500 ppm as converted to phosphate ion of phosphoric acid or an alkali metal hydrogenphosphate, and having a content ratio of acetic acid/alkali metal acetate of 0.1 to 1 and the flow characteristic that the extrusion rate does not substantially increase for at least 10 hours in the relationship between the heating time and the extrusion rate with a capillary rheometer (Koka Flow Tester) at at least one temperature 10.degree. to 80.degree. C. above the melting point.

Abstract: The present invention relates to resin compositions and laminates using saponified ethylene-vinyl acetate copolymers containing a polyether component. Formed products and laminates obtained from the resin compositions are flexible, excellent in flexural fatigue resistance and gas barrier properties and extremely useful as flexible laminates.

Abstract: There is provided a laminate having good gas barrier properties which comprises at least one barrier layer of modified ethylene-vinyl alcohol copolymer containing 0.1 to 5 mol % of pyrrolidone ring-containing units and 20 to 55 mol % of ethylene units, with the degree of saponification of the vinyl acetate component being at least 98 mol %, and at least one layer of thermoplastic resin. This laminate is superior in drawability, and can be made by drawing into bottles, cups, and the like which exhibit excellent clarity, appearance, and gas barrier properties.

Abstract: There is provided a coating material made of a saponification product of a modified ethylene-vinyl acetate copolymer containing a cross-linkable olefinically unsaturated monomer. The saponification product is characterized by its intrinsic viscosity not greater than 0.7 dl/g which is measured at 20.degree. C. using phenol containing 15 wt % of water as a solvent. This polymer is readily soluble in solvents, and the resulting solution can have concentration as high as 20 to 50 wt % and provide coating film which is as strong as that obtained from the conventional EVOH having a high degree of polymerization.

Abstract: A melt molding material which comprises a saponified product of a silicon-containing ethylene-vinyl acetate copolymer. When this melt molding material is formed into a sheet, said sheet is excellent in extensibility and thus suitable for deep forming. The decrease in gas barrier properties is small even under high moisture conditions, and its stress cracking resistance is excellent.

Abstract: Cationic emulsions are obtained by the emulsion polymerization or copolymerization of ethylenically unsaturated monomers such as vinyl acetate, etc. in the presence of a cationic group-modified polyvinyl alcohol (PVA). Typical cationic group-modified PVA are the modified PVA's which contain a copolymeric unit having one of the following formulas: ##STR1## wherein R.sup.1 is H or lower alkyl; B is ##STR2## R.sup.2, R.sup.3 and R.sup.4 are each lower alkyl (substituted or unsubstituted) and X is an anion forming a salt with the ammonium N; and A is an inert bivalent organic group linking the N atom in B to the N atom in the amide group; ##STR3## wherein, in formulas (II) and (III), R.sup.5, R.sup.6 and R.sup.7 are each H, lower alkyl or phenyl; R.sup.8 is lower alkyl; and Y is an anion forming a salt with the imidazolinium N atom. Particularly desirable are the cationic group-modified PVA's containing the copolymeric unit (I) wherein A is ##STR4## R.sup.2, R.sup.3 and R.sup.