Title:
PRODUCTION OF POLYVINYL ALCOHOL RICH IN HETEROTACTICITY
Document Type and Number:
Japanese Patent JP3758856
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To produce a polyvinyl alcohol having a high heterotacticity (mr triplet) in an easier manner by polymerizing a specific vinyl ester in a specific solvent followed by saponification.
SOLUTION: (A) A vinyl ester of formula I (R4 and R5 are each a 1-6C hydrocarbon; R6 is a 1-6C hydrocarbon or H) (e.g. vinyl pivalate) is polymerized in (B) a solvent comprising 10-90 vol.% of a fluorine-containing branched alcohol of formula II [R1 and R2 are each a (chlorine-substituted) fluorinated hydrocarbon; R3 is a (fluorinated) hydroarbon, F, Cl or H] having pKa of 4 or more and less than 10 [e.g. perfluoro-tert-butanol (pKa=5.2)] at -100 to 60°C optionally in the presence of a radical polymerization initiator, a sensitizer or the like, and subsequently the product is saponified to obtain the objective polyvinyl alcohol having heterotacticity (mr triplet) of 50% or more.
Inventors:
Kazunobu Yamada
Yoshio Okamoto
Tamaki Nakano
Sawamoto Mitsuo
Chiba Kitahata
Kazutoshi Terada
Daiji Ida
Yoshiaki Kano
Soki Yoshiki
Okano Zendo
Masamichi Nishimura
Yoshio Okamoto
Tamaki Nakano
Sawamoto Mitsuo
Chiba Kitahata
Kazutoshi Terada
Daiji Ida
Yoshiaki Kano
Soki Yoshiki
Okano Zendo
Masamichi Nishimura
Application Number:
JP19487198A
Publication Date:
March 22, 2006
Filing Date:
July 09, 1998
Export Citation:
Assignee:
Japan Chemical Technology Strategy Promotion Organization
International Classes:
C08F2/06; C08F16/06; C08F8/12; C08F18/04; (IPC1-7): C08F16/06; C08F2/06; C08F8/12; C08F18/04
Domestic Patent References:
| JP11147913A | ||||
| JP5059115A | ||||
| JP4115213A | ||||
| JP4081407A |
Attorney, Agent or Firm:
Toshio Nishizawa
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