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Process for the production of water-insoluble fibers of cellulose monoesters of maleic acid, succinic acid and phthalic acid, having an extremely high absorbability for water and physiological liquids

  • US 4,734,239 A
  • Filed: 03/03/1986
  • Issued: 03/29/1988
  • Est. Priority Date: 04/02/1983
  • Status: Expired due to Fees
First Claim
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1. Process for the production of water-insoluble fibers of cellulose monoesters of maleic acid, succinic acid or phthalic acid having an extremely high absorption ability of water and physiological liquids, comprising, in order:

  • (a) preparing a solution of activated cellulose in dimethylacetamide or 1-methyl-3-pyrrolidon,(b) reacting the so-dissolved cellulose while extensively maintaining average degree of polymerization of 300-800, with a dicarboxylic acid anhydride in a mol ratio from 1 ;

    0.20 up to 1 ;

    4 at 20°

    to 120°

    C. and in the presence of a known esterification catalyst, over a period from 5 minutes to 20 hours to obtain a degree of esterification,(c) spinning the obtained cellulose monoester solution by means of wet spinning into a coagulation agent to form water-insoluble fibers of cellulose monoesters of maleic acid, succinic acid, or phthalic acid, and converting said fibers partially or completely into corresponding fiber-shaped salts of the cellulose monoesters of phthalic acid, maleic acid, or succinic acid in a substantially organic solvent by reaction with alkali metal hydroxide and/or alkali metal alcoholate or ammonia or primary or secondary amine.

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