A three-dimensional electrospun nanofiber scaffold for use in repairing a defect in a tissue substrate is provided. The scaffold includes a flexible deposited fiber network of varying density including a first and second set of set of electrospun fibers. The second set of electrospun fibers is coupled to the first. A first portion of the flexible deposited fiber network includes a higher density of fibers than a second portion of the flexible deposited fiber network, and the tensile strength of first portion is higher than that of the second portion. The scaffold is sufficiently flexible to facilitate application of scaffold to uneven surfaces of the tissue substrate, and enables movement of the scaffold by the tissue substrate. The first and second set of fibers are configured to degrade within three months after application, and each fiber of the deposited fiber network has a diameter of 1-1000 nanometers.

A polylactic acid nano-fiber membrane and preparation method thereof. In particular, the membrane has PLA nanofibers with an average diameter between 50 nm and 200 nm, wherein the nanofibers contain a crystal phase with a volume fraction between 45% and 85% and the crystal phase contains PLA stereocomplex crystals with a volume fraction between 85% and 95%. The method of preparation includes mixing dried PDLA and PLLA in a specific PLLA/PDLA ratio of between 95/5 and 99/1; producing continuous fibers or nonwovens in a extrusion and spinning device, and producing woven fabrics or nonwovens with the continuous fibers; heat treating the woven fabrics or nonwovens; washing the heat treated woven fabrics or nonwovens with a solvent; removing the solvent and drying the woven fabrics or nonwovens; and pressing the dried woven fabrics or nonwovens for making the membrane.

A polylactic acid nano-fiber membrane and preparation method thereof. In particular, the membrane has PLA nanofibers with an average diameter between 50 nm and 200 nm, wherein the nanofibers contain a crystal phase with a volume fraction between 45% and 85% and the crystal phase contains PLA stereocomplex crystals with a volume fraction between 85% and 95%. The method of preparation includes mixing dried PDLA and PLLA in a specific PLLA/PDLA ratio of between 95/5 and 99/1; producing continuous fibers or nonwovens in a extrusion and spinning device, and producing woven fabrics or nonwovens with the continuous fibers; heat treating the woven fabrics or nonwovens; washing the heat treated woven fabrics or nonwovens with a solvent; removing the solvent and drying the woven fabrics or nonwovens; and pressing the dried woven fabrics or nonwovens for making the membrane.

A filter media of purifying air by collecting floating particles in the air can achieve high dust collecting efficiency, low pressure loss, and a long life cycle. In an air cleaner, a filter media included in an air cleaning filter and cleaning air is constituted with a resin fiber of a mean fiber diameter of 3.6 m to 16.5 m, and a ratio of weight per unit area to the mean fiber diameter of the filter media is from 1010.sup.6 g/m.sup.3 to 2010.sup.6 g/m.sup.3.

A filter media of purifying air by collecting floating particles in the air can achieve high dust collecting efficiency, low pressure loss, and a long life cycle. In an air cleaner, a filter media included in an air cleaning filter and cleaning air is constituted with a resin fiber of a mean fiber diameter of 3.6 m to 16.5 m, and a ratio of weight per unit area to the mean fiber diameter of the filter media is from 1010.sup.6 g/m.sup.3 to 2010.sup.6 g/m.sup.3.

A nonwoven fabric including fibers formed from a thermoplastic resin is provided. The thermoplastic resin is an aromatic polysulfone resin. An average fiber diameter of the fibers is 3 m or more and 8 m or less. A basis weight is 5 g/m.sup.2 or more and 30 g/m.sup.2 or less.

A method for producing a nonwoven fabric is provided. The method includes spinning a molten aromatic polysulfone resin from a nozzle and extending it with a high temperature fluid ejected at high speed, thereby obtaining the aromatic polysulfone resin in a fibrous form, and collecting the aromatic polysulfone resin obtained in a fibrous form on a moving collecting member. The aromatic polysulfone resin has a melt mass flow rate of 130 g/10 min or more under conditions of a test temperature of 400 C. and a nominal load of 2.16 kg, which is determined based on ASTM D 1238. A distance from the nozzle to the collecting member is set to 30 mm or less.

The present disclosure relates to a preparation method of a super absorbent polymer non-woven fabric and super absorbent polymer fibers prepared therefrom. According to the preparation method of the present disclosure, it is possible to provide super absorbent polymer fibers exhibiting high flexibility and fast absorption rate in the form of long fibers.

The present disclosure relates to a preparation method of a super absorbent polymer non-woven fabric and super absorbent polymer fibers prepared therefrom. According to the preparation method of the present disclosure, it is possible to provide super absorbent polymer fibers exhibiting high flexibility and fast absorption rate in the form of long fibers.

Nanofiber filter media ribbons are flexible elongate strips of polymeric material having a surface on which is formed an array of nanofibers. Ribbons are formable into woven or non-woven mats. The array of nanofibers can be configured to filter a predetermined contaminant from a fluid stream passing through the mats. Filter ribbons are formable by applying a moldable polymer to a first angular location of a rotating cylindrical roll having an array of nanoholes formed in a circumferential surface thereof so that the polymer covers the surface of the roll and infiltrates the nanoholes; cooling the polymer while rotating the polymer-covered roll to a second angular position; and removing the cooled polymer from the roll as an elongate film having an array of nanofibers formed on a surface thereof by the polymer that infiltrated the nanoholes.