Abstract: The present invention concerns a process for making a polyareneazole multifilament yarn comprising: a) extruding a solution comprising polyareneazole polymer and polyphosphoric acid through a plurality of orifices to produce filaments; b) forming a multifilament yarn from said filaments; c) hydrolyzing at least some of the polyphosphoric acid in the yarn by heating the yarn to a temperature above about 120° C. for up to about two minutes; d) washing at least some of the hydrolyzed polyphosphoric acid from the yarn; e) drying the washed yarn; f) optionally, heating the yarn above about 300° C., and g) collecting the yarn at a speed of at least about 50 meters per minute.

Abstract: The present invention relates to processes for removing phosphorus from a fiber or yarn.

Abstract: The present invention relates to processes for hydrolyzing polyphosphoric acid in a fiber and the removal of hydrolyzed polyphosphoric acid from the fiber.

Abstract: Disclosed are thermal processes for increasing polyareneazole inherent viscosities.

Abstract: The present invention concerns a process for making a polyareneazole polymer comprising the steps of: a) contacting azole-forming monomers, metal powder, and optionally P2O5, in polyphosphoric acid to form a mixture; b) blending the mixture at a temperature of from about 50° C. to about 110° C.; c) further blending the mixture at a temperature of up to about 145° C. to form a solution comprising an oligomer; d) optionally, degassing the solution; and e) reacting the oligomer solution at a temperature of about 160° C. to about 250° C. for a time sufficient to form a polymer.

Abstract: Disclosed are processes for preparing polyareneazole polymers including contacting a molar excess of a free base in water with a terephthalic acid salt to form an aqueous mixture, adjusting the pH to precipitate a monomer complex, contacting the monomer complex with metal powder, and polymerizing the monomer complex. Polyareneazoles, filaments and yarns are also disclosed.

Abstract: Disclosed are processes for preparing polyareneazole polymers that include contacting, in polyphosphoric acid, azole-forming monomers and metal powder, the metal powder added in an amount of from about 0.05 to about 0.9 weight percent, based on the total weight of the azole-forming monomers, and reacting the azole-forming monomers to form the polyareneazole polymers. Polyareneazoles, filaments and yarns are also disclosed.

Abstract: The present invention relates to processes for hydrolyzing polyphosphoric acid in spun multifilament yarns.

Abstract: The present invention concerns a process for making a polyareneazole multifilament yarn comprising: a) extruding a solution comprising polyareneazole polymer and polyphosphoric acid through a plurality of orifices to produce filaments; b) forming a multifilament yarn from said filaments; c) hydrolyzing at least some of the polyphosphoric acid in the yarn by heating the yarn to a temperature above about 120° C. for up to about two minutes; d) washing at least some of the hydrolyzed polyphosphoric acid from the yarn; e) drying the washed yarn; f) optionally, heating the yarn above about 300° C., and g) collecting the yarn at a speed of at least about 50 meters per minute.

Abstract: A process for making a PPD-T fiber having an elongation to break of greater than 7%.

Abstract: A process for preparing subdenier fibers and structures thereof from isotropic polymer solutions is disclosed. The process comprises extruding a stream of the polymer solution into a chamber, introducing a pressurized gas into the chamber, directing the gas in the flow direction of and in surrounding contact with the stream within the chamber, passing both the gas and the stream into a zone of lower pressure at a velocity sufficient to attenuate the stream and fragment it into fibers, and contacting the fragmented stream in the zone with a coagulating fluid.

Abstract: A process for preparing high modulus, high tenacity fibers of aromatic polyamide wherein a first constant tension within 40-95% of the fiber breaking load is applied to washed fibers at a temperature of less than 50.degree. C. for a duration of greater than 5 seconds, and drying the fibers at a second constant tension which is from 10-100% of the first constant tension and at a temperature of more than the temperature of the first constant tension and less than 350.degree. C. until the fibers have a moisture content of about 2 to 10%.

Abstract: Process for preparing subdenier fiber and structures thereof from lyotropic liquid crystalline polymers comprising extruding a stream of the polymer into a chamber, introducing a pressurized gas into the chamber, directing the gas in the flow direction of and in surrounding contact with the stream within the chamber, passing both the gas and the stream into a zoner of lower pressure at a velocity sufficient to attenuate the stream and fragment it into fibers, and contacting the fragmented stream in the zone with a coagulating fluid.