Kuraray Co., Ltd.

Masako Katayama

Keisuke Morikawa

Osamu Kazeto

Masaki Kato

Tatsuya Tanida

Kazuyori Yoshimi

Kazuyuki Somemiya

Yoko Nakano

Kentaro Yoshida

Syunji Tago

Yoshiko Sho, Legal Representative

Yukiko Sho, Legal Representative

Provided is an ethylene-vinyl alcohol copolymer with an ethylene unit content of 15 to 60 mol % and a saponification degree of 85 mol % or more.

Ethylene-(vinyl alcohol) copolymer and method for producing same

An ethylene-vinyl alcohol copolymer may have 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 %. A block character of ethylene units in the ethylene-vinyl alcohol copolymer may be 0.90 to 0.99. Such an ethylene-vinyl alcohol copolymer may have excellent high-speed coating ability and water-resistant adhesiveness, particularly when being used as an adhesive.

Ethylene-vinyl alcohol copolymer, method for producing same, and use thereof

A saponified ethylene-vinyl acetate resin, containing from 0.1 to 3000 ppm of a compound having a molecular weight of at most 1000 and having at least one conjugated double bond, an alkoxy group content of from 0.0005 to 1 mol %, an ethylene content of from 5 to 60 mol %, and a degree of saponification of at least 85 mol % has good melt extrusion stability, drawdown resistance, interlayer adhesion and gas barrier properties, and products made therefrom have good surface smoothness. The saponified ethylene-vinyl acetate resin may be produced by polymerizing a mixture of ethylene and vinyl acetate in the presence of a polymerization initiator having an alkoxy group, thereby producing an ethylene-vinyl acetate copolymer, adding a compound having a molecular weight of at most 1000 and at least one conjugated double bond to the ethylene-vinyl acetate copolymer, then saponifying the ethylene-vinyl acetate copolymer, thereby forming a saponified ethylene-vinyl acetate copolymer.

Saponified, alkoxyl group-containing ethylene-vinyl acetate copolymer and its processed products

The present invention provides a new dispersion stabilizer that satisfies, at a high level, the performances required for a dispersion stabilizer used for suspension polymerization. A method of producing a dispersion stabilizer that is useable for suspension polymerization of a vinyl compound and contains a vinyl alcohol polymer (A) includes producing the vinyl alcohol polymer (A) by heat-treating a vinyl alcohol polymer (B) at a temperature of 90 to 180&#xb0; C. for 0.5 to 20 hours in an atmosphere in which an oxygen concentration is 8000 ppm or lower. The vinyl alcohol polymer (B) has a saponification degree of at least 60 mol % and contains a residual acetic acid group whose block character is in the range of 0.3 to 0.6.

Dispersion stabilizer for suspension polymerization of vinyl compound and method of producing the same

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Kurashiki, Japan

Masako Katayama