Patent · US Expired

Late addition of supplemental ethylene glycol in the preparation of copolyesters

US6103859A · kind A · utility

35Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 18, 1998
Grant dateAug 15, 2000
Priority date
Expiry dateMar 18, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G63/78
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The invention is directed to a method for making copolyesters of terephthalic acid and a diol component including ethylene glycol and includes the steps of adding terephthalic acid and diol to a first esterification reactor and then late addition of supplemental ethylene glycol subsequent to the first esterification reactor but prior to a point where the ethylene glycol partial pressure is reduced below about 300 torr.

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