Title:
NEW POLYVINYL ALCOHOL
Document Type and Number:
Japanese Patent JP3161801
Kind Code:
B2
Abstract:
PURPOSE: To obtain polyvinyl alcohol, having the viscosity-average molecular weight, molecular weight distribution and peak position of the maximum molecular weight satisfying specific conditions, capable of providing excellent film strength and toughness in forming the film and good in operating efficiency.
CONSTITUTION: The objective polyvinyl alcohol (hereinafter referred to as PVA) has (A) ≥200, preferably 200-5000, more preferably 300-3000 viscosity-average molecular weight, (B) ≥10 ratio (molecular weight distribution; Pw/Pn) of the weight-average polymerization decree (Pw) to the number-average polymerization degree (Pn) and (C) the peak position of the maximum molecular weight at ≥3500 polymerization degree in the molecular weight distribution measured by the gel permeation chromatography. This PVA is produced by blending, e.g. a paste of polyvinyl esters separately polymerized so as to provide different polymerization degrees and then saponifying the blend to 30-100mol%, preferably 50-100mol% saponification degree. The PVA causes the deterioration in viscosity within a high-shearing rate region and exhibits shear thinning properties.
Inventors:
Hirotoshi Miyazaki
Naoki Fujiwara
Kazutoshi Terada
Tetsuya Katayama
Shigeki Takada
Hitoshi Maruyama
Naoki Fujiwara
Kazutoshi Terada
Tetsuya Katayama
Shigeki Takada
Hitoshi Maruyama
Application Number:
JP8965892A
Publication Date:
April 25, 2001
Filing Date:
March 13, 1992
Export Citation:
Assignee:
KURARAY CO.,LTD.
International Classes:
C08F8/12; C08F16/02; C08F16/06; (IPC1-7): C08F8/12; C08F16/06
Domestic Patent References:
| JP3177434A | ||||
| JP5410388A | ||||
| JP3287630A | ||||
| JP61283526A | ||||
| JP477542A | ||||
| JP6239648A |