(US20160326336) A dispersion spun fluoropolymer fiber prepared from non-melt-processible polytetrafluoroethylene particles and aluminum oxide particles. The concentration of Al2O3 in the aqueous dispersion may range from between about 0.1% to about 5%, with specific concentration of 0.1%, 1.0. The aqueous dispersion is mixed with an aqueous matrix polymer solution containing a matrix polymer and then extruded into a coagulation bath containing a concentration of ions which coagulate the matrix polymer to form an intermediate fiber structure which carries ionic species. The intermediate fiber structure is sintered to decompose the matrix polymer and coalesce the polytetrafluoroethylene particles and the Al2O3 particles into a blended fiber. The resulting, blended fluoropolymer fiber exhibits improved properties relative to 100% dispersion spun polytetrafluoroethylene fibers.
(US20160108557) A fluoropolymer fiber exhibiting improved wear properties prepared from a blend of fluoropolymer particles and aluminum oxide particles. The concentration of aluminum oxide particles in the blend ranges from between about 0.1% to about 5%, with a specific concentration of 0.1% to 1.0%. The fluoropolymer fibers may be dispersion spun, melt spun or paste extruded.
(US20150183898) The present invention provides an aqueous dispersion of a low-molecular-weight polytetrafluoroethylene (PTFE), which contains an easily removable surfactant, and has a good dispersion stability. Specifically, the present invention provides an aqueous dispersion of a low-molecular-weight PTFE comprising tetrafluoroethylene (TFE) units, or TFE units and modifying monomer units which are copolymerizable with the TFE units, wherein the aqueous dispersion contains from 70 to 9,000 ppm, based on the aqueous dispersion, of a fluorine-containing compound of the formula (1) below: X—(CF2)m—Y (1) where X is H or F; m is an integer from 3 to 5; and Y is —SO3M, —SO4M, —SO3R, —SO4R, —COOM, —PO3M2 or —PO4M2, M being H, NH4 or an alkali metal, and R being an alkyl group having 1 to 12 carbons, and the low-molecular-weight PTFE has an average primary particle size of from 100 to 350 nm.