| 摘要 |
PROBLEM TO BE SOLVED: To provide a new method for producing polyvinyl acetoacetal. SOLUTION: The method for producing a polyvinyl acetoacetal, in which the weight ratio of a cis type vinyl acetoacetal part/a trans type vinyl acetoacetal part in the acetoacetal part of a polyvinyl acetoacetal is 1-4, comprises an acetalization reaction process of effecting an acetalization reaction between a polyvinyl alcohol and acetaldehyde in a water solvent in a reactor, a reaction product discharge process of discharging a reaction product from the reactor after the attainment of the acetoacetalization degree of the formed polyvinyl acetoacetal to at least 11 wt.% and an aging reaction process of subjecting the discharged reaction product to an aging reaction in a reactor different from the above reactor. COPYRIGHT: (C)2009,JPO&INPIT
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