The present invention relates to a preparation method of para-aramid nanofibers, and belongs to the technical field of novel polymer materials. The para-aramid nanofibers prepared in the present invention have a diameter of 10-100 nm, and a length of hundreds of microns. The preparation method includes: adding a certain amount of surfactant in a PPTA low-temperature polymerization process, and controlling aggregation of PPTA molecules along with growth of a PPTA molecule chain, thereby preparing the para-aramid fibers with a uniform size and an adjustable nano-scale diameter under assistance of other means (e.g., a coagulator and high-speed shearing dispersion). The present invention is short in production process and simple in equipment, can realize stable batch production to meet needs of large-scale production of the para-aramid nanofibers, has wide application prospects and can be applied to preparing a lithium-ion battery separator, a high-performance composite material and the like.

Described herein are apparatuses and methods of creating fibers, such as microfibers and nanofibers for the production of clothing items and footwear. Also described herein is a microfiber and/or nanofiber coating system having a support that holds an object to be coated by fibers during the coating process. The support may move the object with respect to the fibers, such that at least a portion of each of the exterior surfaces of the object are coated by the fibers formed by the microfiber and/or nanofiber coating system.

Described herein are apparatuses and methods of creating fibers, such as microfibers and nanofibers for the production of clothing items and footwear. Also described herein is a microfiber and/or nanofiber coating system having a support that holds an object to be coated by fibers during the coating process. The support may move the object with respect to the fibers, such that at least a portion of each of the exterior surfaces of the object are coated by the fibers formed by the microfiber and/or nanofiber coating system.

A process for the recovery and recycling of unreacted monomer in a one-step process for the production of a carbon-fiber precursor. An integrated and improved single-step process for the production of a carbon-fiber precursor is also described, which starts from the co-monomers and reaches the spinning step obtaining the final precursor fiber, which provides for the recovery of the unreacted monomers at the end of the polymerization step and their recycling to the polymerization process itself.

A method of recycling a mixed textile, wherein the method comprises: i) supplying the mixed textile, wherein the mixed textile comprises cellulosic fibers and synthetic fibers, wherein the synthetic fibers comprise at least one synthetic plastic, ii) at least partially depleting the synthetic plastic from the cellulose, and iii) further processing the depleted mixed textile after depleting.

A method of recycling a mixed textile, wherein the method comprises: i) supplying the mixed textile, wherein the mixed textile comprises cellulosic fibers and synthetic fibers, wherein the synthetic fibers comprise at least one synthetic plastic, ii) at least partially depleting the synthetic plastic from the cellulose, and iii) further processing the depleted mixed textile after depleting.

A filament fibre production method having process steps of: filtration of and/or applying an evaporation process to wastewater containing a polyvinyl alcohol polymer from a sizing process and/or a painting process in a manner to contain polyvinyl alcohol polymer at rate of 20-30% by mass, adding carbonyl di-imidazole and ethylenediamine or 3-chloro-propionyl chloride and ethylendiamine into wastewater comprising polyvinyl alcohol polymer in 20-30% rate as a result of filtration and/or evaporation process and obtaining PVA-ethylendiamine hydrogel solvent, adding dimethyl sulfoxide, boric acid, acetic acid and a surface active agent into a solvent bath containing PVA-ethylendiamine hydrogel solvent at 20-30% rate, applying coagulation process to obtained PVA-ethylendiamine hydrogel solvent with acetone of critic fluid phase, stretching polyvinyl alcohol polymer passing through coagulation bath at 200 C.?-250 C.? temperature range when wet, and subjecting to fixing process.

A filament fibre production method having process steps of: filtration of and/or applying an evaporation process to wastewater containing a polyvinyl alcohol polymer from a sizing process and/or a painting process in a manner to contain polyvinyl alcohol polymer at rate of 20-30% by mass, adding carbonyl di-imidazole and ethylenediamine or 3-chloro-propionyl chloride and ethylendiamine into wastewater comprising polyvinyl alcohol polymer in 20-30% rate as a result of filtration and/or evaporation process and obtaining PVA-ethylendiamine hydrogel solvent, adding dimethyl sulfoxide, boric acid, acetic acid and a surface active agent into a solvent bath containing PVA-ethylendiamine hydrogel solvent at 20-30% rate, applying coagulation process to obtained PVA-ethylendiamine hydrogel solvent with acetone of critic fluid phase, stretching polyvinyl alcohol polymer passing through coagulation bath at 200 C.?-250 C.? temperature range when wet, and subjecting to fixing process.

An embodiment is a method of recycling carbon fibers that includes: preparing a carbon fiber reinforced plastic formed product that includes a carbon fiber reinforced plastic containing a carbon fiber and a resin; thermally decomposing or dissolving the resin in the carbon fiber reinforced plastic formed product by a first heating process or a first dissolving process; and winding while drawing the carbon fiber from the carbon fiber reinforced plastic formed product after the first heating process or the first dissolving process. The winding further includes thermally decomposing or dissolving a residue of the resin attached to the carbon fiber by a second heating process or a second dissolving process and adding a sizing agent to the carbon fiber after the second heating process or the second dissolving process.

An embodiment is a method of recycling carbon fibers that includes: preparing a carbon fiber reinforced plastic formed product that includes a carbon fiber reinforced plastic containing a carbon fiber and a resin; thermally decomposing or dissolving the resin in the carbon fiber reinforced plastic formed product by a first heating process or a first dissolving process; and winding while drawing the carbon fiber from the carbon fiber reinforced plastic formed product after the first heating process or the first dissolving process. The winding further includes thermally decomposing or dissolving a residue of the resin attached to the carbon fiber by a second heating process or a second dissolving process and adding a sizing agent to the carbon fiber after the second heating process or the second dissolving process.