Method of stabilizing fluorine-containing polymer
US6451962B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 2001 |
| Grant date | Sep 17, 2002 |
| Priority date | — |
| Expiry date | May 3, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2327/12
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
To provide the stabilization method, in which unstable groups of melt-processable fluorine-containing polymer having unstable groups can be stabilized rapidly and effectively, and even if the obtained stabilized polymer is melt-molded, an obtained molded article is free from bubbles and cavity and no coloration arises. The method of stabilizing a fluorine-containing polymer by melt-kneading a melt-processable fluorine-containing polymer having unstable groups in a kneader having a stabilization treatment zone which satisfies the following conditions:(1) an oxygen-containing gas is present in the stabilization treatment zone,(2) water is present in the stabilization treatment zone, and(3) an absolute pressure in the stabilization treatment zone is adjusted to a pressure of 0.2 MPa or more or (a) an oxygen-containing gas is present in the stabilization treatment zone in a sufficient amount that the fluorine-containing polymer after the stabilization treatment has the number of carbon radical spins measured by an electron spin resonance absorption analysis at a temperature of 77 K of not more than 5×1013 spin/g, and (b) water is present in the stabilization treatment zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.