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Catalyzed interfacial polycondensation polycarbonate process

  • US 4,515,936 A
  • Filed: 04/16/1984
  • Issued: 05/07/1985
  • Est. Priority Date: 04/16/1984
  • Status: Expired due to Fees
First Claim
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1. A method of producing aromatic polycarbonate by a catalyzed interfacial polycondensation polycarbonate process comprising(1) forming an agitated two-phase admixture comprising(i) an organic phase containing an inert organic solvent and a polycondensation catalyst,(ii) an aqueous phase containing dissolved therein an aromatic dihydroxy compound, a strong base and an ionic surfactant in a quantity of from about 100 to 1,000 parts per million having a pH of at least 11 subject to the proviso that(a) the volume ratio of inert organic solvent phase to aqueous phase is within the range of from about 0.04:

  • 1 to 0.20;

    1 and(b) the mole ratio of base to aromatic dihydroxy compound is at least about 0.25;

    1,(2) adding and reacting a carbonyl halide with the aromatic dihydroxy compound to form an aromatic polycarbonate having a weight average molecular weight of at least about 2000, and(3) separating and recovering the solid aromatic polycarbonate particulate from the liquid aqueous phase.

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