E.i. Dupont De Nemours and Company

E. I. Du Pont De Nemours

Hung H Yang

Michael W Bowen

Minshon J Chiou

Hamid M Ghorashi

Charles King

Stanley R Cochran

John C Coburn

A process for preparing a textile fiber of sulfonated poly(p-phenylene terephthalamide) that is rapidly dyeable to deep shades.

Process of making textile fibers of sulfonated poly(p-phenylene

An oriented, shaped article comprising at least about 55% and less than about 80% by weight of a first polymer phase of at least one lyotropic polymer and at least about 20% and less than about 45% by weight of a second polymer phase of at least one thermally-consolidatable polymer and consolidated parts made therefrom.

Oriented, shape articles of lyotropic/thermally-consolidatable polymer

A textile fiber of sulfonated poly(p-phenylene terephthalamide) that is rapidly dyeable to deep shades.

Textile fibers of sulfonated poly(p-phenylene terephthalamide)

A process for spinning para-aramid fibers of increased tenacity and elongation at break by using an air-gap means with a spinneret capillary of less than 2.5 mils diameter, a coagulation bath temperature of less than 10C, and tension on the fibers during washing and drying of more than 0.05 and less than 0.35 gpd.

Method for spinning para-aramid fibers of high tenacity and high

Oriented, shaped articles such as films or fibers of para-aramid/meta-aramid blends which ar useful for the manufacture of para-aramid pulp, a process for making such articles and a pulp-making process are disclosed.

Oriented, shaped articles of pulpable para-aramid/meta-aramid blends

Process for making aromatic polyamide fibers of high hydrolytic stability is disclosed. The polyamide is a copolymer including chloroterephthalamide or a blend of homopolymers including one with chloroterephthalamide; and the fibers are dried under tension or heat treated.

Process for making fibers with improved hydrolytic stability

A process is disclosed for preparing high tenacity, high modulus, para-aramid fibers by application of cyclic tensioning forces to such fibers in the newly-spun, wet, state before they have been dried.

Cyclic tensioning of never-dried yarns

A process for making oriented, shaped articles of para-aramid/thermally-consolidatable polymer blends by orienting spinnable dopes containing 10 to 25% by weight fiber-forming polymers being at least about 55% and less than about 80% para-aramid and at least about 20% and less than about 45% thermally consolidatable polymer in a common solvent and removing the solvent.

Process for making oriented, shaped articles of

Aromatic polyamide fibers of high hydrolytic stability are disclosed. The polyamide is a copolymer including chloroterephthalamide or a blend of homopolymers including one with chloroterephthalamide; and the fibers are dried under tension or heat treated.

Yarn with improved hydrolytic stability from aromatic polyamide

Poly(p-phenyleneterephthalamide) yarn of improved fatigue resistance is prepared.

Poly(p-phenyleneterephthalamide) yarn of improved fatigue resistance

Poly(p-phenyleneterephthalamide) yarn of improved fatigue resistance is prepared by spinning the polymer in sulfuric acid through an air gap into an aqueous coagulating bath to produce a coagulated yarn, maintaining the coagulating bath at a temperature of at least 20.degree. C., washing and neutralizing the yarn while it is under a tension of from 0.2 to 0.4 grams per denier, and drying the yarn at a temperature below 200.degree. C. while it is maintained under a tension of 0.05 to 0.2 grams per denier.

Method of preparing poly (p-phenyleneterephthalamide) yarns of improved

Directly spinning highly oriented staple fibers of para-aramids using a dry-jet wet-spinning process in which the filaments in the gap between the spinneret and the coagulating fluid are attenuated with a liquid jetted symmetrically about the filaments at a rate sufficient to break the filaments intermittently to form staple length fibers that taper along their length from an enlarged head.

Aramid staple and pulp prepared by spinning

Aromatic polyamide filaments of higher strength are obtained by drying air-gap spun filaments under tension while controlling the moisture content of the dried filaments.

Yarn drying process

Improved aromatic polyamide fibers from aromatic polyamides whose chain-extending bonds are either coaxial or parallel and oppositely directed are obtained by dry spinneret wet spinning into a shallow coagulating bath having an orifice in its bottom for removal of coagulating liquid and fibers wherein no more than a minor portion of coagulating liquid is lower than the entrance of the bath orifice in the proximity of the bath orifice. Preferably, no more than 10% of the coagulating liquid is lower than the entrance of the bath orifice and most preferably none of the coagulating liquid is lower than the entrance of the bath orifice.

Spinning process

A process for preparing high strength, high modulus aromatic polyamide filaments by extruding an acid solution containing at least 30 g. per 100 acid of an aromatic polyamide having an inherent viscosity of at least 4 and chain extending bonds which are either coaxial or parallel and oppositely directed through a layer of inert noncoagulating fluid into a coagulating bath and then through a spin tube along with overflowing coagulating liquid is improved by jetting additional coagulating liquid symmetrically about the filaments in a downward direction forming an angle .theta. or 0.degree. to 85.degree. with respect to the filaments within 2.0 milliseconds from the time the filaments enter the spin tube, the flow rates of both the jetted and overflowing coagulating liquid being maintained at a constant rate such that their momentum ratio .phi. is from 0.5 to 6.0 and the mass flow rate of total coagulating liquid is from 70 to 200 times the mass flow rate of the filaments.

Growing community of inventors

Richmond, VA, United States of America

Hung H Yang