Spinning low fluorosurfactant fluoropolymer dispersions
US7985361B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2008 |
| Grant date | Jul 26, 2011 |
| Priority date | — |
| Expiry date | Oct 3, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/3154
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for dispersion spinning non-melt-processible fluoropolymer fiber in which a mixture of an aqueous dispersion of non-melt-processible polytetrafluoroethylene or modified polytetrafluoroethylene fluoropolymer particles and an aqueous solution of matrix polymer is formed. The non melt-processible particles have an SSG of less than about 2.40. The aqueous dispersion contains an aliphatic alcohol ethoxylate nonionic surfactant having a 20% residuals temperature determined by thermogravimetric analysis (TGA) of less than about 290° C. and is essentially free of surfactants containing aromatic groups. The dispersion has a fluorinated surfactant content of less than about 300 ppm. The mixture is extruded into a coagulation bath containing a concentration of ions which coagulate the matrix polymer to form an intermediate fiber structure. The intermediate fiber structure is sintered to decompose the matrix polymer and coalesce. The present invention also provides a spinning composition useful for the dispersion spinning of non-melt-processible fluoropolymer fiber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.