JP2002284818A5

JP2002284818A5 -

Info

Publication number: JP2002284818A5
Application number: JP2001375398A
Authority: JP
Filing date: 2001-12-10
Publication date: 2005-07-21
Anticipated expiration: 2021-12-10

Description

次いで、該溶液をメタノールで希釈して濃度３０％に調整してニーダーに仕込み、溶液温度を４０℃に保ちながら、水酸化ナトリウムの２％メタノール溶液を共重合体中の酢酸ビニル（Ａ）１モルに対して８ミリモルとなる量を加えてケン化及び脱炭酸を行った。ケン化及び脱炭酸が進行すると共にケン化物が析出し、遂には粒子状となった。生成したポリビニルアルコールを濾別し、メタノールでよく洗浄して熱風乾燥機中で乾燥し、目的物を得た。 Next, the solution was diluted with methanol to adjust the concentration to 30% and charged into a kneader, and while maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to vinyl acetate (A) 1 in the copolymer. It was saponified and decarboxylated by adding an amount of 8 mmol Le moles. As the saponification and decarboxylation proceeded, the saponified product was precipitated and finally became particulate. The produced polyvinyl alcohol was separated by filtration, washed well with methanol and dried in a hot air dryer to obtain the desired product.

次いで、該溶液をメタノールで希釈して濃度３０％に調整してニーダーに仕込み、溶液温度を４０℃に保ちながら、水酸化ナトリウムの２％メタノール溶液を共重合体（Ａ−Ｂ）中の酢酸ビニル（Ａ）１モルに対して９ミリモルとなる量を加えてケン化及び脱炭酸を行った。ケン化及び脱炭酸が進行すると共にケン化物が析出し、遂には粒子状となった。生成したポリビニルアルコールを濾別し、メタノールでよく洗浄して熱風乾燥機中で乾燥し、目的物を得た。 Next, the solution was diluted with methanol to adjust the concentration to 30% and charged into a kneader, and while maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to the acetate in the copolymer (AB). It was saponified and decarboxylated by addition of vinyl (a) an amount to be 9 mmol Le per 1 mol. As the saponification and decarboxylation proceeded, the saponified product was precipitated and finally became particulate. The produced polyvinyl alcohol was separated by filtration, washed well with methanol and dried in a hot air dryer to obtain the desired product.

次いで、該溶液をメタノールで希釈して濃度３０％に調整してニーダーに仕込み、溶液温度を４０℃に保ちながら、水酸化ナトリウムの２％メタノール溶液を共重合体（Ａ−Ｃ）中の酢酸ビニル（Ａ）１モルに対して９ミリモルとなる量を加えてケン化を行った。ケン化が進行すると共にケン化物が析出し、遂には粒子状となった。
かかるケン化物を３Ｎの塩酸（水／メタノール＝１／１の混合溶媒）中に分散させ、６０℃で脱ケタール化を行い、生成したポリビニルアルコールを濾別し、メタノールでよく洗浄して熱風乾燥機中で乾燥し、目的物を得た。 Next, the solution was diluted with methanol to adjust the concentration to 30% and charged into a kneader, and while maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to the acetate in the copolymer (AC). It was saponified by the addition of vinyl (a) an amount to be 9 mmol Le per 1 mol. As the saponification progressed, the saponified product was precipitated and finally became particulate.
The saponified product was dispersed in 3N hydrochloric acid (mixed solvent of water / methanol = 1/1), de-ketalized at 60 ° C., the produced polyvinyl alcohol was filtered off, washed well with methanol, and dried with hot air. It was dried in the machine to obtain the desired product.

次いで、該溶液をメタノールで希釈して濃度４０％に調整してニーダーに仕込み、溶液温度を４０℃に保ちながら、水酸化ナトリウムの２％メタノール溶液を共重合体中の酢酸ビニル（Ａ）１モルに対して９ミリモルとなる量を加えてケン化を行った。ケン化が進行すると共にケン化物が析出し、遂には粒子状となった。
かかるケン化物を濾別し、メタノールでよく洗浄して熱風乾燥機中で乾燥し、目的物を得た。 Next, the solution was diluted with methanol to adjust the concentration to 40% and charged into a kneader, and while maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to vinyl acetate (A) 1 in the copolymer. It was saponified by adding an amount of 9 mmol Le moles. As the saponification progressed, the saponified product was precipitated and finally became particulate.
The saponified product was separated by filtration, washed well with methanol and dried in a hot air dryer to obtain the desired product.

次いで、該溶液をメタノールで希釈して濃度４０％に調整してニーダーに仕込み、溶液温度を４０℃に保ちながら、水酸化ナトリウムの２％メタノール溶液を共重合体中の酢酸ビニル（Ａ）１モルに対して１０ミリモルとなる量を加えてケン化を行った。ケン化が進行すると共にケン化物が析出し、遂には粒子状となった。
かかるケン化物を濾別し、メタノールでよく洗浄して熱風乾燥機中で乾燥し、目的物を得た。 Next, the solution was diluted with methanol to adjust the concentration to 40% and charged into a kneader, and while maintaining the solution temperature at 40 ° C., a 2% methanol solution of sodium hydroxide was added to vinyl acetate (A) 1 in the copolymer. It was saponified by adding an amount of 10 mmol Le moles. As the saponification progressed, the saponified product was precipitated and finally became particulate.
The saponified product was separated by filtration, washed well with methanol and dried in a hot air dryer to obtain the desired product.