Patent · US Expired

Method of producing thermotropic liquid crystalline copolyester, thermotropic liquid crystalline copolyester composition obtained by the same method, and molding made of the same composition

US6296950A · kind A · utility

3Cited by
6References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 15, 2001
Grant dateOct 2, 2001
Priority date
Expiry dateMar 15, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31989
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A method of producing a thermotropic liquid crystalline copolyester having an extremely small amount of out-gases comprising the steps of: (1) charging in a reactor 5-100 mol % of aromatic hydroxycarboxylic acid, 0-47.5 mol % of aromatic dicarboxylic acid and 0-47.5 mol % of aromatic diol, so that the sum of mol % of each material is 100 mol % and the molt of aromatic dicarboxylic acid and that of aromatic diol are substantially equal; (2) adding acetic anhydride of an amount which satisfies the formula, (B-C)/A.gtoreq.1.04, "A" representing the total molar number of the hydroxy group in a reaction system, "B" representing the molar number of acetic anhydride to be added, and "C" representing the molar number of water present in the reaction system prior to addition of acetic anhydride; (3) acetylation; (4) melt polymerization; and (5) solid-phase polymerization.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.