Modified polytetrafluoroethylene fine powder and method for the production of the same
US6531557B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1999 |
| Grant date | Mar 11, 2003 |
| Priority date | — |
| Expiry date | Mar 12, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F214/262
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A modified polytetrafluoroethylene fine powder containing agglomerates of colloidal particles with an average particle size of from 0.05 to 0.5 &mgr;m which comprise a copolymer of tetrafluoroethylene and an olefin-monomer represented by X(CF2)nOCF═CF2 in which X is a hydrogen atom, a fluorine atom or a chlorine atom, and n is an integer of 1 to 6, and/or C3F7(OCF2CF2CF2)m[OCF(CF3)CF2]pOCF═CF2 in which m and p are independently an integer of 0 to 4, provided that the sum of m and p is not 0 (zero), a content of the olefin monomer being from 0.02 to 0.3 wt. %, wherein the copolymer has a molecular weight distribution Mw/Mn of from 1.5 to 4.5 and a standard specific gravity of from 2.135 to 2.175. This modified polytetrafluoroethylene has good paste extrudability, and provides molded articles having good mechanical properties, in particular, pressure resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.