Charged polymeric webs, such as electret webs, include a thermoplastic resin and a charge-enhancing additive. The additives are substituted heterocyclic thiolate salts. The heterocyclic thiolate salt has 2 nitrogen groups and a third group that may be an NH, N—NH.sub.2, O, or S group. The substituent group is an aromatic or heterocyclic aromatic group. The electret webs may be a non-woven fibrous web or a film. The electret webs are suitable for use as filter media.

Provided are a sub-micron fibrous membrane in which sub-micron fibers aligned along one axis and sub-micron fibers in a random pattern form a network, and a method for producing the sub-micron fibrous membrane.

A gas filtering medium is composed of hydrophobic polyester fiber as from 20-80% by total weight of textile fibers and 80-20% by total weight of hydrophilic textile fibers and a microfibrillated cellulose fiber in a weight/weight ratio of 1.5-8.5/100 parts by weight of total textile fiber.

A fiber can be made having a structure with an axial core and a coating layer. The fiber can have a polymer core and one or two layers surrounding the core. The fine fiber can be made from a polymer material and a resinous aldehyde composition such that the general structure of the fiber has a polymer core surrounded by at least a layer of the resinous aldehyde composition.

An electrospun nanofiber membrane and a method for preparing the electrospun nanofiber membrane are provided to solve problems of poor mechanical properties, short service life, poor uniformity and consistency of orientation of fibers and poor stability of fiber networks in current electrospun composite nanofiber materials. The electrospun nanofiber membrane is prepared by spinning solution through a high-voltage electrospinning device. The spinning solution is blending solution of regenerated silk fibroin: polyvinyl alcohol: polylactic acid with a mass ratio being 75-85:10-20:5 dissolved in a mixed solvent of trifluoroacetic acid and dichloromethane with a volume ratio being 7:3. The method establishes a reasonable mass ratio parameter of the regenerated silk fibroin, the polyvinyl alcohol and the polylactic acid to blending spinning to improve spinnability of silk fibroin, as well as prepare the electrospun composite nanofiber membrane with good mechanical properties.

A solid fiber is described, where the solid fiber is characterized by (a) a modification degree Do/Di, in a cross section of the solid fiber of 1.20 to 8.50 where the inscribed circle diameter is denoted by Di and the circumscribed circle diameter is denoted by Do; and (b) a porous specific surface area of not less than 30 m.sup.2/g.

The present invention provides a chargeable sheath/core-structured fiber that contains a polypropylene-based resin as a main resin, wherein the sheath part contains (a) a carboxylic anhydride-modified polyolefin and (b) at least one antioxidant selected from the group consisting of a combined antioxidant a phenolic antioxidant and a phosphorus-based antioxidant, and sulfur-based antioxidants; and (c) an oil containing a polyoxyalkylene alkyl ether represented by the general formula (I) as a finishing oil is deposited on the outer surface of the sheath part, and that can satisfy heat resistance and charge retainability. (In the formula, R.sup.1 represents a saturated or unsaturated aliphatic hydrocarbon group having 10 to 30 carbon atoms; R.sup.2 represents a hydrogen atom or a methyl group; and k is an integer of 1 to 4.)

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An embolic filter balloon is disclosed. The embolic filter balloon may comprise an inflatable balloon portion. Further, the inflatable balloon portion may be coupled to a filter member. The embolic filter balloon may be disposed in a body lumen. In some embodiments, the embolic filter balloon may be configured such that when the inflatable balloon portion is at least partially inflated the filter member extends at least partially across the body lumen. Such a configuration may allow the embolic filter balloon, when deployed, to filter particles greater than a predetermined size from a fluid in the body lumen.

An electrospun nanofiber membrane and a method for preparing the electrospun nanofiber membrane are provided to solve problems of poor mechanical properties, short service life, poor uniformity and consistency of orientation of fibers and poor stability of fiber networks in current electrospun composite nanofiber materials. The electrospun nanofiber membrane is prepared by spinning solution through a high-voltage electrospinning device. The spinning solution is blending solution of regenerated silk fibroin:polyvinyl alcohol:polylactic acid with a mass ratio being 75-85:10-20:5 dissolved in a mixed solvent of trifluoroacetic acid and dichloromethane with a volume ratio being 7:3. The method establishes a reasonable mass ratio parameter of the regenerated silk fibroin, the polyvinyl alcohol and the polylactic acid to blending spinning to improve spinnability of silk fibroin, as well as prepare the electrospun composite nanofiber membrane with good mechanical properties.

Provided is an electrospinning alignment apparatus enabling mass production of nanofiber membranes by simultaneously nanofibers that are spun in alignment in one direction on a transferred carrier and nanofibers that are randomly spun.