Process for manufacturing polyester copolymers
US5539078A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1994 |
| Grant date | Jul 23, 1996 |
| Priority date | — |
| Expiry date | Dec 14, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/189
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention is an improved process for producing polyester copolymers, which employs a combination of an acid-based process and an ester-based process. The ester-based process is used to manufacture a low molecular weight naphthalate-based polymer, and the acid-based process is used to manufacture phthalate-based oligomers. The low molecular weight naphthalate-based polymer is combined with the phthalate-based oligomers, or the raw materials used to form the phthalate-based oligomers, to form a random polyester copolymer. Specifically, the process of the invention may be employed to manufacture, in an ester-based process, a low molecular weight polyethylene naphthalate polymer, which is then combined with polyethylene terephthalate oligomers produced in an acid-based process, and the acid-based process is then used to continue the polymerization reaction. Ester interchange reactions and further polymerization result in the production of a random polyethylene terephthalate/naphthalate copolymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.