The invention provides networked polymeric nanofibers having a structure in which amorphous polymeric fibers are branched at multiple sites and having a diameter of from 1 nanometer to 100 nanometers.

A solution of a polymer such as polystyrene in a good solvent thereof is rapidly frozen to form a nanoscale phase-separation structure of the polymer and the frozen solvent. The networked polymeric nanofibers can then be obtained upon removing the frozen solvent.

A composite filament includes a core particle comprising a styrene/acrylate polymer resin, and a shell comprising a styrene/acrylate ionomer resin, wherein the styrene/acrylate ionomer resin comprises a metal ion acrylate monomer, and methods of making thereof. Various articles can be manufactured from such composite filaments.

A composite filament includes a core particle comprising a styrene/acrylate polymer resin, and a shell comprising a styrene/acrylate ionomer resin, wherein the styrene/acrylate ionomer resin comprises a metal ion acrylate monomer, and methods of making thereof. Various articles can be manufactured from such composite filaments.

Methods of making polycationic nanofibers by grafting cationic polymers onto electrospun neutral nanofibers and polycationic nanofibers produced by the methods are provided herein. In addition, methods of using the polycationic nanofibers to reduce inflammation, to adsorb anionic compounds such as heparin or nucleic acids, to inhibit the growth of microbes or inhibit the formation of a biofilm are also provided. The polycationic nanofibers may be in a mesh and may be included in a medical device, wound dressing, bandage, or as part of a graft.

Methods of making polycationic nanofibers by grafting cationic polymers onto electrospun neutral nanofibers and polycationic nanofibers produced by the methods are provided herein. In addition, methods of using the polycationic nanofibers to reduce inflammation, to adsorb anionic compounds such as heparin or nucleic acids, to inhibit the growth of microbes or inhibit the formation of a biofilm are also provided. The polycationic nanofibers may be in a mesh and may be included in a medical device, wound dressing, bandage, or as part of a graft.

A method for treating an oil spill includes providing a polystyrene-based sorbent in the form of polystyrene microfibers having a sorption capacity in the range of between 30 g/g to 217 g/g, measured as grams of oil sorbed per one gram of the sorbent; drenching the polystyrene microfibers in the oil spill to be treated; collecting the oil drenched polystyrene microfibers; and removing excess oil from the oil drenched polystyrene microfibers by compressing the microfibers. The method further includes dissolving the oil drenched polystyrene microfibers in a petroleum-based solvent in the form of gasoline having an octane number of ninety one, in which both the oil drenched polystyrene microfibers and the oil is soluble, thereby forming a solution comprising the gasoline having dissolved therein the polystyrene microfibers and the oil; and utilizing the solution as a feedstock for feeding a refinery.

A method for treating an oil spill includes providing a polystyrene-based sorbent in the form of polystyrene microfibers having a sorption capacity in the range of between 30 g/g to 217 g/g, measured as grams of oil sorbed per one gram of the sorbent; drenching the polystyrene microfibers in the oil spill to be treated; collecting the oil drenched polystyrene microfibers; and removing excess oil from the oil drenched polystyrene microfibers by compressing the microfibers. The method further includes dissolving the oil drenched polystyrene microfibers in a petroleum-based solvent in the form of gasoline having an octane number of ninety one, in which both the oil drenched polystyrene microfibers and the oil is soluble, thereby forming a solution comprising the gasoline having dissolved therein the polystyrene microfibers and the oil; and utilizing the solution as a feedstock for feeding a refinery.

The invention provides networked polymeric nanofibers having a structure in which amorphous polymeric fibers are branched at multiple sites and having a diameter of from 1 nanometer to 100 nanometers. A solution of a polymer such as polystyrene in a good solvent thereof is rapidly frozen to form a nanoscale phase-separation structure of the polymer and the frozen solvent. The networked polymeric nanofibers can then be obtained upon removing the frozen solvent.

The invention provides networked polymeric nanofibers having a structure in which amorphous polymeric fibers are branched at multiple sites and having a diameter of from 1 nanometer to 100 nanometers. A solution of a polymer such as polystyrene in a good solvent thereof is rapidly frozen to form a nanoscale phase-separation structure of the polymer and the frozen solvent. The networked polymeric nanofibers can then be obtained upon removing the frozen solvent.

The method for producing wet spun fibers/a wet formed film using a double-walled pipe type micronozzle apparatus according to the present invention is a production method, wherein, in a step of extruding an internal phase comprising a fiber/film material and a good solvent for the fiber/film material in a linear form from the circular/rectangular end of the internal pipe of the apparatus into an external phase comprising a poor solvent for the fiber/film material, the external phase flowing in the external pipe of the apparatus, the ratio of the external phase flow rate to the internal phase flow rate is set to 1 or more, and further for the wet spun fibers, the external phase line speed at the orifice portion at which the internal phase and the external phase merge is set to 0.1 ms.sup.1 or more.