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Methylene-crosslinked polyarylamine and process for preparing same

  • US 5,053,539 A
  • Filed: 01/17/1991
  • Issued: 10/01/1991
  • Est. Priority Date: 04/11/1990
  • Status: Expired due to Term
First Claim
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1. A process for preparing a methylene-crosslinked polyarylamine by reacting aniline with formalin in the presence of hydrochloric acid under the following conditions (a), (b), (c) and (d):

  • (a) the amount of hydrochloric acid is in the range of from 0.1 to 0.5 mole per mole of aniline;

    (b) the amount of aniline is in the range of from 1.5 to 4.0 moles per mole of formalin;

    (c) the reaction is divided in at least four stages, andthe reaction in the first stage is carried out at 20 to 50°

    C. in a water/aniline ratio in the range of from 1.3 to 2.5 moles,the reaction in the second stage is done at 40 to 70°

    C. in a water/aniline ratio in the range of from 1.9 to 5.0 moles,the reaction in the third stage is done at 50 to 90°

    C. in a water/aniline ratio in the range of from 2.4 to 5.7 moles, andthe reaction in the last stage is done at a temperature of 110°

    C. or more; and

    (d) formalin is divided into 3 or more stages and used in the reactions in the respective stages.

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