The present disclosure is to provide a method for producing polyurethane (PU) nanofibers with significantly improved hydrophilicity by producing water-soluble polymer/PU blend nanofiber by coaxial-electrospinning water-soluble polymer and hydrophobic PU, and, subsequently, dissolving and removing the water-soluble polymer from the blend nanofiber in water.

Provided is a polyurethane elastic fiber wherein surface treating agents do not bleed even after lengthy storage, thereby preventing contamination of packing material, and which exhibits stable friction performance independent of storage duration, making the fiber suitable for a stable gathered member with low occurrence of core slip-back. This polyurethane elastic fiber is a multifilament polyurethane elastic fiber and is characterized by having, in the multifilament cross section, a void part demarcated by the constituent individual filaments being in contact with one another and by having a cross-sectional void part area ratio of 15% to 60% as calculated according to the formula (cross-sectional void part area ratio [%])=100(area of the void part)/(total cross-sectional area), where the total cross-sectional area is the sum of the area of the void part and the cross-sectional areas of all individual filaments that constitute the multifilament.

A sound absorbing body comprises a non-woven fabric or a non-woven fabric laminate, the non-woven fabric or the non-woven fabric laminate comprises a fiber that has an average fiber diameter of less than 3,000 nm, the non-woven fabric or the non-woven fabric laminate has a thickness of less than 10 mm, the non-woven fabric or the non-woven fabric laminate has a unit thickness flow resistance of greater than 4.0 E+06 Ns/m.sup.4 and less than 5.0 E+08 Ns/m.sup.4, and the non-woven fabric or the non-woven fabric laminate has a bulk density of greater than 70 kg/m.sup.3 and less than 750 kg/m.sup.3.

A sound absorbing body comprises a non-woven fabric or a non-woven fabric laminate, the non-woven fabric or the non-woven fabric laminate comprises a fiber that has an average fiber diameter of less than 3,000 nm, the non-woven fabric or the non-woven fabric laminate has a thickness of less than 10 mm, the non-woven fabric or the non-woven fabric laminate has a unit thickness flow resistance of greater than 4.0 E+06 Ns/m.sup.4 and less than 5.0 E+08 Ns/m.sup.4, and the non-woven fabric or the non-woven fabric laminate has a bulk density of greater than 70 kg/m.sup.3 and less than 750 kg/m.sup.3.

The present disclosure is relates to an artificial leather and a method of manufacturing the same. The manufacturing method of the artificial leather includes steps in which TPU particles are provided. The method continues with step in which the TPU particles are heated to be melted. The method continues with step in which a first TPU mesh layer is formed by meltblowing the melted TPU. The method continues with step in which a second TPU mesh layer is meltblown on the first TPU mesh layer so as to form a multi-layer TPU mesh layer structure. The method continues with step in which the multilayer TPU mesh layer structure is heat pressed to form the artificial leather.

A coated substrate is disclosed, including a solvent-sensitive substrate and a polyester coating disposed on the solvent-sensitive substrate, wherein the polyester coating includes a polyester copolymer of a polyol and a polyacid. A method for forming a coated substrate is disclosed including spraying solvated polyester material from a spray nozzle onto a solvent-sensitive substrate and drying the solvated polyester material to form a polyester disposed on the solvent-sensitive substrate, wherein the solvated polyester material and the polyester coating include a polyester copolymer of a polyol and a polyacid.

A coated substrate is disclosed, including a solvent-sensitive substrate and a polyester coating disposed on the solvent-sensitive substrate, wherein the polyester coating includes a polyester copolymer of a polyol and a polyacid. A method for forming a coated substrate is disclosed including spraying solvated polyester material from a spray nozzle onto a solvent-sensitive substrate and drying the solvated polyester material to form a polyester disposed on the solvent-sensitive substrate, wherein the solvated polyester material and the polyester coating include a polyester copolymer of a polyol and a polyacid.

An enzyme responsive shape memory polymer formed from a glassy, cross-linked shape memory polymer that incorporates ester bonds that are responsive to the present of an enzyme. PCL-based polyurethanes (featuring simple alternation of PCL diol and lysine-based diisocyanate) are degradable by Amano lipase PS. A non-degradable thermoplastic elastomer may be dual electrospun with a polycaprolactone based TPU with the fixing phase compressed so that the composite is ready for enzymatically triggered contraction. Alternatively, the elastomer may be a PCL copolymer-based polyurethane amorphous elastomer that is both degradable and elastomeric and put into compression so that upon enzymatic degradation of the elastomeric phase the scaffold expands.

An enzyme responsive shape memory polymer formed from a glassy, cross-linked shape memory polymer that incorporates ester bonds that are responsive to the present of an enzyme. PCL-based polyurethanes (featuring simple alternation of PCL diol and lysine-based diisocyanate) are degradable by Amano lipase PS. A non-degradable thermoplastic elastomer may be dual electrospun with a polycaprolactone based TPU with the fixing phase compressed so that the composite is ready for enzymatically triggered contraction. Alternatively, the elastomer may be a PCL copolymer-based polyurethane amorphous elastomer that is both degradable and elastomeric and put into compression so that upon enzymatic degradation of the elastomeric phase the scaffold expands.

The present invention generally relates to the design and manufacture of nanofiber layers, webs, films, or membranes that may be self-supporting and can function as standalone products. More particularly, the present invention relates to a microporous nanofiber films and the use of such films in a wide variety of products and applications, including applications where physical property tuning is typically limited. Generally, the microporous films of the present invention can function as a standalone nanofiber membrane or can be bonded to other microporous films to produce a layered stacked film stack with customizable properties. Unlike conventional microporous films available in today's market, the microporous films of the present invention can be lighter, require less raw material cost to produce, and can improve operating performances in a variety of applications.