A process for producing a polymer strand involves: inserting a nucleation element into a pre-strand composition, the pre-strand composition comprising a polymer mixed with a solvent, the polymer having a concentration in the pre-strand composition that is greater than or equal to an overlap concentration (c*) of the polymer in the pre-strand composition; and, withdrawing the nucleation element from the pre-strand composition so that a strand comprising the polymer is pulled by the nucleation element from the pre-strand composition, the nucleation element being withdrawn at a rate such that a pull time (τ.sub.pull) of the nucleation element is less than reptation time (τ.sub.rep) required to relax polymer entanglements in the pre-strand composition, thereby inducing a viscoelastic response in the pre-strand composition as the strand is pulled by the nucleation element from the pre-strand composition.

Fibrous elements, such as filaments and/or fibers, and more particularly to fibrous elements that contain a non-hydroxyl polymer, fibrous structures made therefrom, and methods for making same are provided.

Fibrous elements, such as filaments and/or fibers, and more particularly to fibrous elements that contain a non-hydroxyl polymer, fibrous structures made therefrom, and methods for making same are provided.

To provide a polyurethane elastic yarn that is superior in unwinding properties and adhesive properties in respect to a hot melt adhesive agent, and to provide a manufacturing method thereof. A polyurethane elastic yarn wherein the main structural component of the polyurethane is a polymer diol or diisocyanate; and includes a polymer that includes, as the main structural unit, a structural unit that uses an aromatic olefin and/or an aliphatic diolefin as a monomer, and is partially hydrogenated or completely hydrogenated.

A gas diffusion layer for proton exchange membrane fuel cell and preparation method thereof are provided. The preparation method is to papermake and dry carbon fiber suspension mainly composed of a fibrous binder, water, a dispersant and carbon fibers with different aspect ratios to obtain a carbon fiber base paper, and then carbonize and graphitize under the protection of nitrogen or inert gas to obtain a gas diffusion layer for proton exchange membrane fuel cell; where the fibrous binder is a composite fiber or a blend fiber composed of a phenolic resin and other resin; where the prepared gas diffusion layer for proton exchange membrane fuel cell has a pore gradient, and the layer with the smallest pore size is an intrinsic microporous layer.

A gas diffusion layer for proton exchange membrane fuel cell and preparation method thereof are provided. The preparation method is to papermake and dry carbon fiber suspension mainly composed of a fibrous binder, water, a dispersant and carbon fibers with different aspect ratios to obtain a carbon fiber base paper, and then carbonize and graphitize under the protection of nitrogen or inert gas to obtain a gas diffusion layer for proton exchange membrane fuel cell; where the fibrous binder is a composite fiber or a blend fiber composed of a phenolic resin and other resin; where the prepared gas diffusion layer for proton exchange membrane fuel cell has a pore gradient, and the layer with the smallest pore size is an intrinsic microporous layer.

The polymeric composition of this invention can be used as a temporary support material in the additive manufacturing of three dimensional articles without compromising the quality of the ultimate product, reducing printing speed, increasing cost, increasing the incidence of printer jamming, or requiring printers of increased complexity. This invention more specifically discloses a polymeric composition which is particularly useful as a temporary support material for utilization in three-dimensional printing, said polymeric composition being comprised of a first polymeric component which is suitable for use as a modeling material and a second polymeric component which is immiscible with the first polymeric component, wherein the polymeric composition has a continuous phase, wherein the continuous phase is comprised of the second polymeric component, and wherein the polymeric composition has a Shore A hardness of at least 80.

A method of wet spinning poly (3,4-ethylenedioxythiopene):poly (styrenesulfonate) or PEDOT:PSS fibers produces PEDOT:PSS fibers having a unique combination of electrical conductivity, thermal conductivity and Young's modulus properties.

A crystalline silicon carbide fiber containing silicon carbide and boron nitride, the crystalline silicon carbide fiber having a content of Si of 64% to 72% by weight, a content of C of 28% to 35% by weight, and a content of B of 0.1% to 3.0% by weight, and including, at a surface portion, a composition gradient layer in which a content of silicon carbide increases while a content of boron nitride decreases toward a depth direction.

The present invention provides a preparation method preparation method for three-layer artificial blood vessel and application thereof. The three-layer artificial blood vessel comprise three layers, electrospinning inner layer, dense middle layer and electrospinning outer layer, the three-layer structure is closely combined and difficult to separate. The inner layer with a cytoskeleton-like structure can promote the formation of intima; the dense middle layer can effectively prevent the leakage of biomacromolecules and increase the puncture resistance of the whole artificial blood vessel; and the outer layer can promote the growth of tissue cells and better integrate with tissue. The three-layer artificial blood vessel provided by the invention has excellent blood compatibility, good flexibility, good puncture resistance and interlayer peeling resistance. The preparation method is convenient and is suitable for industrial scale production.