Production process and production apparatus for polybutylene terephthalate
US6359106B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 2000 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Aug 22, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/183
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polybutylene terephthalate having good heat stability and excellent hydrolysis resistance is continuously produced in a series of a first reactor for reacting an aromatic dicarboxylic acid comprising terephthalic acid as a main ingredient or a derivative thereof with a glycol comprising 1,4-butanediol as a main ingredient, thereby producing an oligomer with an average degree of polymerization of 2.2 to 5, a second reactor for polycondensating the oligomer from the first reactor, thereby preparing a low polymerization product with an average degree of polymerization of 25 to 40, and a third reactor for further polycondensating the low polymerization product from the second reactor, thereby producing a high molecular weight polyester with an average degree of polymerization of 70 to 130, or followed by a fourth reactor for further polycondensing the polyester from the third reactor to an average degree of polymerization of 150 to 200, thereby producing a high molecular weight polyester. Another third reactor or a plurality of third reactors can be provided in parallel to the third reactor, thereby producing different kinds of polybutylene phthalate with different degrees of polymeriz…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.