Production of polyester fibers of improved stability
US4374960A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1981 |
| Grant date | Feb 22, 1983 |
| Priority date | — |
| Expiry date | Sep 16, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K5/0008
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
There is provided by this invention a process for the production of high molecular weight linear polyethylene terephthalate condensation polyesters which are useful especially for preparing specialty fibers which have excellent resistance to degradation so that they can be used in such commercial articles as paper making machine fabric, industrial belting, etc. The improved high molecular weight linear polyethylene terephthalate condensation polyester specialty fibers are characterized by improved hydrolytic stability and by reduction in the free carboxyl content so as to have a carboxyl concentration of less than about 6 gram equivalents per 10.sup.6 grams of the polyester. These polyester specialty fibers are prepared by the steps of adding an end capping reagent to particles of the said feed polymer, heating to obtain a homogeneous mixture of the said polyester and end capping reagent, mechanically working the polyester melt, and forming filaments of the linear polyester having a reduced free carboxyl content.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.