Kuraray Co., Ltd.

Kazunori Watanabe

Susumu Matsunaga

Kenichi Hamada

Yasuo Tokitoh

Kozo Tamura

Takashi Hori

Hiroshi Oshima

Hideaki Oka

Yoshio Fuchigami

Tatsufumi Watanabe

Fumio Nakahara

Masaji Kato

Tomoyasu Tsuda

Junji Funakoshi

Jun Nagai

Tatsuo Morotomi

Tsuyoshi Kowaka

Hiroyuki Miyawaki

Masatoshi Yanagawa

The present invention relates to a method of obtaining a (meth)acrylate-based polymer from a reaction solution containing the (meth)acrylate-based polymer, the method including (a) adding an acid to the reaction solution containing the (meth)acrylate-based polymer which is obtained by polymerizing a monomer composed mainly of a (meth)acrylate in a water-insoluble organic solvent in the presence of a metal compound, (b) washing the reaction solution to which the acid has been added by admixing water at 90&#xb0; C. or more, (c) separating the mixed solution of the reaction solution and water generated by the washing in (b) into an organic solvent solution layer and an aqueous solution layer, and (d) isolating each of the organic solvent solution layer and the aqueous solution layer in order to obtain the (meth)acrylate-based polymer from the isolated organic solvent solution layer.

Method of taking (meth)acrylic ester polymer out of liquid reaction mixture

A method of producing polyvinyl alcohol polymer, with which a high-strength polyvinyl alcohol polymer with a high degree of saponification can be obtained, the polyvinyl ester saponification process can be linked directly with the spinning process, in which the polyvinyl alcohol polymer is made into fiber, the mole ratio of alcohol with respect to the polyvinyl alcohol can be freely selected, and the concentration of the polyvinyl alcohol obtained by the saponification reaction is high. The polyvinyl alcohol polymer that is obtained by this method exhibits a high block character value and is excellent in randomness is provided, wherein a polyvinyl ester is subject to a saponification reaction in an alcohol-containing organic solvent under the presence of a saponification catalyst and the saponification is carried out while distilling off the carboxylic acid ester that is produced by the saponification reaction.

Polyvinyl alcohol polymer production method and polyvinyl alcohol polymer

A method of producing carboxylic acid and alcohol, that includes: supplying a liquid to a first distillation tower, said liquid including a carboxylic acid ester, and said first distillation tower being operated in a total reflux condition, to obtain a side stream; supplying said side stream to a hydrolysis reactor that includes an acid catalyst to obtain a reaction product liquid that includes a carboxylic acid, an alcohol, water and a carboxylic acid ester; supplying said reaction product liquid to said first distillation tower and removing a first bottom liquid therefrom, said first bottom liquid including a carboxylic acid, an alcohol and water; supplying said first bottom liquid to a second distillation tower and separating said first bottom liquid into a first top distillate that includes an alcohol, and a second bottom liquid that includes a carboxylic acid and water; supplying said second bottom liquid to a third distillation tower and separating said second bottom liquid into a second top distillate that includes a carboxylic acid and water, and a third bottom liquid that includes a carboxylic acid; circulating said second top distillate back to a tower top of said first distillation tower, and adding water to said tower top.

Method of producing carboxylic acid and alcohol

A method for producing polyamides, and to a method for producing primary polycondensates which are intermediates for polyamide production. More precisely, the invention relates to a method for producing primary polycondensates, which comprises a step of polycondensing a dicarboxylic acid component having a terephthalic acid content of from 60 to 100 mol % and a diamine component in which the amount of 1,9-nonanediamine and/or 2-methyl-1,8-octanediamine falls between 60 and 100 mol %, in the presence of water of being from 15 to 35% by weight, at a reaction temperature falling between 250.degree. C. and 280.degree. C. and under a reaction pressure (P) that satisfies the following formula (1):

Method for producing polyamides

A process for producing 7-octen-1-al by isomerization of 2,7.octadien-1-ol by feeding 2,7-octadien-1-ol and hydrogen to a reaction zone in the presence of a copper catalyst while controlling the molar ratio of 2,7-octadien-1-ol to hydrogen within a range of 99/1 to 75/25, and effecting isomerization in the gaseous phase. This process ensures a high yield, a high selectivity and stable operation over a long period of time.

Process for producing 7-octen-1-al

The invention provides an industrially advantageous method of separating liquid mixtures which can reduce the liquid film temperature drop in module units. As a result, the separation system can be rendered compact, the treatment capacity can be increased and the cost can be reduced. Thus, the method of the invention is effective in curtailment of separation and purification processes in the chemical industry and in putting high-efficiency membrane separation techniques to practice use. Its industrial utility is very great.

Separation of liquid mixtures

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Kurashiki, Japan

Kazunori Watanabe