Abstract: There is provided a multilayer structure comprising a layer (A) containing an ethylene-vinyl alcohol copolymer having an ethylene unit content of 1 mol % or more and less than 20 mol %, a viscosity-average polymerization degree of 200 to 5000, and a saponification degree of 80 to 99.7 mol %, wherein a block character of ethylene units is 0.90 to 0.99; and a layer (B) containing at least one resin selected from the group consisting of a polyolefin resin, a polyester resin and a polyamide resin. Such a multilayer structure has excellent oxygen-gas barrier performance. In addition, an aqueous solution containing the ethylene-vinyl alcohol copolymer exhibits excellent viscosity stability even after long-term storage. Therefore, even after a long period of time from preparation of the aqueous solution, it can be uniformly applied to a substrate and thus, a multilayer structure having excellent oxygen-gas barrier performance can be provided.

Abstract: A dispersant for suspension polymerization may, even when a usage amount thereof is low, enable obtaining polymer particles having a small average particle diameter with few coarse particles, and having favorable plasticizer absorptivity. Such a dispersant may include a vinyl alcohol polymer having a structure of following formula (1) and satisfy inequality (2) 0.4?[X]×102/[Ra,1]2?3.0??(2). In formula (1), R is a hydrocarbon group having 4 or more carbon atoms. In inequality (2), [X] is a mole percentage content of the structure of formula (1) with respect to total structural units of the vinyl alcohol polymer; and [Ra,1] is an HSP distance ((J/cm3)1/2) between the structure of formula (1) and vinyl chloride.

Abstract: An aqueous emulsion may include: an ethylene-vinyl alcohol copolymer (A) as a dispersant; and a polymer (B) containing an unsaturated ethylenic monomer unit as a dispersoid, wherein the ethylene-vinyl alcohol copolymer (A) has a content of ethylene units of 1 mol % or more and less than 20 mol % and a block character of the ethylene units from 0.90 to 0.99. The aqueous emulsion may contain the ethylene-vinyl alcohol copolymer (A), as a dispersant, having a specific structure and is thus excellent in storage stability at low temperatures and water-resistant adhesiveness.

Abstract: The present invention relates to ethylene-vinyl alcohol copolymer particles, comprising an ethylene-vinyl alcohol copolymer having an ethylene unit content of 1 mol % or more and less than 20 mol %, a viscosity-average polymerization degree of 200 to 5000, and a saponification degree of 80 to 99.99 mol %, wherein a crystallinity in water Cw (30° C.) at 30° C. and a crystallinity in water Cw (70° C.) at 70° C. as determined by pulse NMR satisfy formula (I). There is thus provided ethylene-vinyl alcohol copolymer particles having excellent solubility in water and excellent gas barrier performance.

Abstract: An aqueous emulsion may include: an ethylene-vinyl alcohol copolymer (A) as a dispersant; and a polymer (B) containing an unsaturated ethylenic monomer unit as a dispersoid, wherein the ethylene-vinyl alcohol copolymer (A) has a content of ethylene units of 1 mol % or more and less than 20 mol % and a block character of the ethylene units from 0.90 to 0.99. The aqueous emulsion may contain the ethylene-vinyl alcohol copolymer (A), as a dispersant, having a specific structure and is thus excellent in storage stability at low temperatures and water-resistant adhesiveness.

Abstract: A water-based adhesive for a paper straw, comprising: an ethylene-vinyl alcohol copolymer (A); and water, wherein the ethylene-vinyl alcohol copolymer (A) has a content of ethylene units of 1 mol % or more and less than 20 mol % and a block character of the ethylene units from 0.90 to 0.99. The water-based adhesive contains the ethylene-vinyl alcohol copolymer (A) having a specific structure, and is thus excellent in balance between the rapid coatability, the film strength, the initial adhesiveness, the dynamic water resistance, and the acid resistance, and particularly excellent in the rapid coatability, the film strength, and the acid resistance.

Abstract: The present invention provides an aqueous solution containing an ethylene-vinyl alcohol copolymer (A), an alcohol (B) having 1 to 4 carbon atoms and water (C), wherein an ethylene unit content of the ethylene-vinyl alcohol copolymer (A) is 1 mol % or more and less than 20 mol %; a crystallinity in water Cw (30° C.) at 30° C. and a crystallinity in water Cw (70° C.) at 70° C. as determined by pulse NMR satisfy Formula (I); the ethylene-vinyl alcohol copolymer (A) is contained in 0.1 to 100 parts by mass based on 100 parts by mass of water (C); and the alcohol (B) is contained in 0.01 to 30 parts by mass based on 100 parts by mass of water (C). Thus, there is provided an aqueous solution of an ethylene-vinyl alcohol copolymer, which forms a less number of lumps and generates a reduced amount of fibrillar precipitate even when a shear stress is applied. 4 ? 100 - Cw ? ( 30 ? ° ? ? C . ) 100 × [ Cw ? ( 30 ? ° ? ? C . ) - Cw ? ( 70 ? ° ? ? C .

Abstract: An aqueous emulsion may include an ethylene-vinyl alcohol copolymer (A) as a dispersant and a polymer (B) which contains an ethylenically unsaturated monomer unit as a dispersoid, wherein the ethylene-vinyl alcohol copolymer (A) has an ethylene unit content of 1 mol % or more and less than 20 mol %; and a crystallinity in water at 30° C. (Cw (30° C.)) and a crystallinity in water at 70° C. (Cw (70° C.)) as determined by pulse NMR satisfying formula (I). Such aqueous emulsions can form fewer aggregates and exhibit excellent water-resistant adhesiveness and excellent film formability.

Abstract: An ethylene-vinyl alcohol copolymer may have an ethylene unit content of 1 mol % or more and less than 15 mol %, a saponification degree of 85 mol % or more and less than 99.9 mol %, and a viscosity-average degree of polymerization of 200 or more and less than 3000. The copolymer may contain a molecule containing a structure (I) Y being H or —CH3, at an end; and a molecule containing a structure (II) Z being H or —CH3, at an end, a total content of the structure (I) and the structure (II) in all monomer units is 0.001 mol % or more and less than 0.1 mol %, and a molar ratio R [I/(I+II)] of the structure (I) to the total of the structure (I) and the structure (II) satisfies formula (1): R < 0 . 9 ? 2 - Et / 1 ? 00 , ( 1 ) Et being ethylene unit content (mol %).

Abstract: There is provided a multilayer structure comprising a layer (A) containing an ethylene-vinyl alcohol copolymer having an ethylene unit content of 1 mol % or more and less than 20 mol %, a viscosity-average polymerization degree of 200 to 5000, and a saponification degree of 80 to 99.7 mol %, wherein a block character of ethylene units is 0.90 to 0.99; and a layer (B) containing at least one resin selected from the group consisting of a polyolefin resin, a polyester resin and a polyamide resin. Such a multilayer structure has excellent oxygen-gas barrier performance. In addition, an aqueous solution containing the ethylene-vinyl alcohol copolymer exhibits excellent viscosity stability even after long-term storage. Therefore, even after a long period of time from preparation of the aqueous solution, it can be uniformly applied to a substrate and thus, a multilayer structure having excellent oxygen-gas barrier performance can be provided.

Abstract: The present invention provides a resin material that comprises an ethylene-modified vinyl alcohol polymer as a main component, and that excels in hue, water solubility, and aqueous-solution viscosity stability. The present invention also provides an aqueous solution and an adhesive comprising such a resin material. The present invention relates to a resin material comprising an ethylene-modified vinyl alcohol polymer and sodium acetate, wherein: the ethylene-modified vinyl alcohol polymer has an ethylene unit content of 1 mol % or more and less than 15 mol %, a viscosity-average degree of polymerization of 200 or more and less than 3,000, and a degree of saponification of 80 mol % or more and less than 99.9 mol %, and comprises 0.0005 mol % or more and 0.10 mol % or less of a propyl group at one end of the polymer, and the sodium acetate content is 0.05 mass % or more and less than 2 mass %.

Abstract: The present invention provides an aqueous emulsion excellent in heat resistance, water resistance (particularly, hot water resistance and boiling resistance), and viscosity stability. The present invention also provides an adhesive containing the aqueous emulsion, forming an adhesive layer resistant to staining, and ensuring a high level of safety. The present invention relates to an aqueous emulsion containing an ethylenically unsaturated monomer unit-containing polymer (A) as a dispersoid and vinyl alcohol polymer (B) as a dispersant, wherein, the ethylenically unsaturated monomer unit-containing polymer (A) includes a structural unit derived from a radical-polymerizable ethylenically unsaturated monomer (a) having a functional group represented by the following general formula (W), and the degree of saponification of the vinyl alcohol polymer (B) is 80 mol % or more: wherein, X is an oxygen atom or sulfur atom, and * represents a bond.

Abstract: A modified vinyl alcohol polymer powder having a structural unit derived from a derivative of an ethylenically unsaturated dicarboxylic acid, and containing a reduced amount of methanol, and a trace amount of a component that does not dissolve in water. The present invention relates to a modified vinyl alcohol polymer powder containing a structural unit derived from a derivative (A) of an ethylenically unsaturated dicarboxylic acid in a content (X) of 0.05 mol % or more and 10 mol % or less, and having a degree of saponification of 80.0 mol % or more and 99.9 mol % or less, the modified vinyl alcohol polymer powder has a methanol content of 0.01 weight % or more and less than 3.0 weight %, the modified vinyl alcohol polymer powder contains 0.1 ppm or more and less than 2,000 ppm of a component that is insoluble in a 90° C., 5 weight % aqueous solution.

Abstract: There is provided an ethylene-vinyl alcohol copolymer with an ethylene unit content of 1 mol % or more and less than 20 mol %, a viscosity-average polymerization degree of 200 to 5000 and a saponification degree of 80 to 99.7 mol %, wherein a block character of ethylene units in the ethylene-vinyl alcohol copolymer is 0.90 to 0.99. Such an ethylene-vinyl alcohol copolymer has excellent high-speed coating ability and water-resistant adhesiveness, particularly when being used as an adhesive.

Abstract: The present invention provides a coating agent having a reduced methanol content, an adhesive including the coating agent and excellent in coating performance and adhesiveness, and a coated product including the coating agent and excellent in water resistance and alcohol resistance. The present invention relates to a coating agent comprising a modified vinyl alcohol polymer (A), the modified vinyl alcohol polymer (A) comprising a structural unit derived from a derivative (a) of an ethylenically unsaturated dicarboxylic acid in a content (X) of 0.05 mol % or more and 10 mol % or less, having a degree of saponification of 80.0 mol % or more and 99.9 mol % or less, having a methanol content of less than 3.0 mass % as measured by headspace gas chromatography, and having an amount of 0.1 ppm or more and less than 2,000 ppm of a component insoluble in a 90° C., 5 mass % aqueous solution.

Abstract: The present invention provides an aqueous solution containing an ethylene-vinyl alcohol copolymer (A), an alcohol (B) having 1 to 4 carbon atoms and water (C), wherein an ethylene unit content of the ethylene-vinyl alcohol copolymer (A) is 1 mol % or more and less than 20 mol %; a crystallinity in water Cw (30° C.) at 30° C. and a crystallinity in water Cw (70° C.) at 70° C. as determined by pulse NMR satisfy Formula (I); the ethylene-vinyl alcohol copolymer (A) is contained in 0.1 to 100 parts by mass based on 100 parts by mass of water (C); and the alcohol (B) is contained in 0.01 to 30 parts by mass based on 100 parts by mass of water (C). Thus, there is provided an aqueous solution of an ethylene-vinyl alcohol copolymer, which forms a less number of lumps and generates a reduced amount of fibrillar precipitate even when a shear stress is applied. 4 ? 100 - Cw ? ( 30 ? ° ? ? C . ) 100 × [ Cw ? ( 30 ? ° ? ? C . ) - Cw ? ( 70 ? ° ? ? C .

Abstract: The present invention provides an aqueous emulsion composition excellent in heat resistance, water resistance, hot water resistance, boiling water resistance, and viscosity stability and also excellent in stain resistance. The present invention relates to an aqueous emulsion composition including an aqueous emulsion (D) and a cyclic acid anhydride (E). The aqueous emulsion (D) includes a polymer (X) having an ethylenically unsaturated monomer (B), a polyvinyl alcohol resin (A), and water. At least one selected from the polyvinyl alcohol resin (A) and the polymer (X) has, in a main chain thereof, a structural unit derived from a monomer (C) represented by the following formula (I), (II), (III), or (IV). (The definitions of the symbols in the formulae are omitted.

Abstract: The present invention relates to ethylene-vinyl alcohol copolymer particles, comprising an ethylene-vinyl alcohol copolymer having an ethylene unit content of 1 mol % or more and less than 20 mol %, a viscosity-average polymerization degree of 200 to 5000, and a saponification degree of 80 to 99.99 mol %, wherein a crystallinity in water Cw (30° C.) at 30° C. and a crystallinity in water Cw (70° C.) at 70° C. as determined by pulse NMR satisfy formula (I). There is thus provided ethylene-vinyl alcohol copolymer particles having excellent solubility in water and excellent gas barrier performance.

Abstract: The present invention provides an aqueous emulsion excellent in heat resistance, water resistance (particularly, hot water resistance and boiling resistance), and viscosity stability. The present invention also provides an adhesive containing the aqueous emulsion, forming an adhesive layer resistant to staining, and ensuring a high level of safety. The present invention relates to an aqueous emulsion containing an ethylenically unsaturated monomer unit-containing polymer (A) as a dispersoid and vinyl alcohol polymer (B) as a dispersant, wherein, the ethylenically unsaturated monomer unit-containing polymer (A) includes a structural unit derived from a radical-polymerizable ethylenically unsaturated monomer (a) having a functional group represented by the following general formula (W), and the degree of saponification of the vinyl alcohol polymer (B) is 80 mol % or more: wherein, X is an oxygen atom or sulfur atom, and * represents a bond.

Abstract: Provided is a vinyl alcohol-based copolymer, obtained by saponifying a copolymer of vinyl acetate and a polyfunctional monomer, wherein the polyfunctional monomer contains two or more ethylenic double bonds in its molecule, the vinyl alcohol-based copolymer has a side chain containing an ethylenic double bond and a molar ratio (d) of the ethylenic double bond to a total of vinyl alcohol units and vinyl acetate units is from 0.05/100 to 2/100, and the vinyl alcohol-based copolymer is water soluble.