Formation of melt-spun acrylic fibers possessing a highly uniform internal structure which are particularly suited for thermal conversion to quality carbon fibers
US4935180A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1988 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Aug 25, 2008 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD01F6/18
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An acrylic multifilamentary material possessing an internal structure which is particularly suited for thermal conversion to high strength carbon fibers is formed via a specifically defined combination of processing conditions. The acrylic polymer while in substantially homogeneous admixture with appropriate concentrations (as defined) of acetonitrile and water is melt extruded and is drawn at a relatively low draw ratio which is substantially less than the maximum draw ratio achievable. This fibrous material which is capable of readily undergoing drawing is passed through a heat treatment zone wherein the evolution of residual acetonitrile and water takes place. The resulting fibrous material following such heat treatment is subjected to additional drawing to accomplish further orientation and internal structure modification and to produce a fibrous material of the appropriate denier for carbon fiber production. One accordingly is provided a reliable route to form a fibrous acrylic precursor for carbon fiber production without the necessity to employ the solution-spinning routes commonly utilized in the prior art for precursor formation. One can now eliminate the utilization and h…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.