Process for manufacture of high molecular weight polyester resins from 2,6-naphthalene dicarboxylic acid
US5331082A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1993 |
| Grant date | Jul 19, 1994 |
| Priority date | — |
| Expiry date | Jun 16, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/189
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
High quality linear polyester resin is prepared by reacting in a first step or zone 2,6-naphthalene dicarboxylic acid with a molten prepolymer derived from a glycol and 2,6-naphthalene dicarboxylic acid to form a low molecular weight product of the first step or zone; reacting this resultant product with a glycol in at least two successive steps or zones of glycol addition to form prepolymer; and polymerizing at least a portion of the resulting prepolymer to form polyester resin which exhibits midpoint glass transition temperatures above about 123.degree. C. The resulting prepolymer is particularly suitable for reaction with the 2,6-naphthalene dicarboxylic acid in the first step or zone. Advantageously, at least a portion of the prepolymer is, therefore, returned to the first step or zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.