1171results about "Wet spinning methods" patented technology

Generally, the present invention is directed to, in one embodiment, a method for forming a composite nonwoven web configured to deliver skin wellness agents to the skin of a user. According to the method, an aqueous system of a hydrophilic polymer and a skin wellness agent is formed. The aqueous system is then electrospun onto a surface of a nonwoven web containing synthetic fibers. The resulting nanofibers have an average diameter of from about 50 nanometers to about 5000 nanometers, such as from about 200 nanometers to about 700 nanometers.

Coagulation spinning produces structures such as fibers, ribbons, and yarns of carbon nanotubes. Stabilization, orientation, and shaping of spun materials are achieved by post-spinning processes. Advantages include the elimination of core-sheath effects due to carbonaceous contaminants, increasing mechanical properties, and eliminating dimensional instabilities in liquid electrolytes that previously prohibited the application of these spun materials in electrochemical devices. These advances enable the application of coagulation-spun carbon nanotube fibers, ribbons, and yarns in actuators, supercapacitors, and in devices for electrical energy harvesting.

The invention relates to a process for forming fibers from a spinning solution utilizing a high speed rotary sprayer. The fibers can be collected into a uniform web for selective barrier end uses. Fibers with an average fiber diameter of less that 1,000 nm can be produced.

Said invention discloses a bamboo charcoal viscose fiber and producing method. The bamboo charcoal is finely selected, coarse cracked, dust removed, trash extracted, and pulverized to less than 0.5 micrometer, the bamboo charcoal micropowder and dispersant are put in water to made into aqueous emulsion slurry, filtered four times by two-layer of poplin filter fabric, respectively spinning in filament spinning machine and shorts spinning machine to obtain said bamboo charcoal viscose fiber which has bacteriostasis and antibiotic effect.

The invention relates to a preparation method of ultra-high molecular weight polyethylene fiber, which comprises the following steps: firstly, mixing ultra-high molecular weight polyethylene powder with solvent for swelling to obtain suspending liquid, and then extruding and dissolving the suspending liquid through a double screw extruder to obtain 4-25 percent of spinning solution, wherein the solvent is liquid hydrocarbon under room temperature; secondly, spraying and cooling the spinning solution to obtain gel filament; thirdly, applying 1-10 times of pretensioning to the gel filament, settling the pretensioned gel filament for 12-48h, extracting and drying the gel filament; fourthly, applying 4-130 times of heat drawing to the dried gel filament 70-160 DEG C to obtain the ultra-high molecular weight polyethylene fiber. After the gel filament is formed and pretentioned to a certain degree, the primary filament can be more uniform and has higher tension property , and the ultra-high molecular weight polyethylene fiber with excellent property can be prepared.

An artificial polypeptide fiber of the present invention is an artificial fiber containing a polypeptide as a main component, and has a stress of 350 MPa or more and a toughness of 138 MJ/m³ or more. A method for producing an artificial polypeptide fiber of the present invention is a method for producing the artificial polypeptide fiber obtained by spinning a spinning solution (6) containing a polypeptide derived from natural spider silk proteins and performing drawing of at least two stages. The drawing of at least two stages includes a first-stage drawing (3) in wet heat and a second-stage drawing (4) in dry heat. Thereby, the present invention provides high-toughness artificial polypeptide fibers having favorable stress and rupture elongation, and a method for producing the same.

An apparatus for making electrspun fibers comprises a collector that may be submerged in a coagulation bath. The collector may be automatically movable between a first position and a second position, wherein at least a portion of the collected fibers are submerged in a coagulation bath in the first position and spaced apart from the coagulation bath in the second position. The collector may be a rotating collector. A process for making electrospun fibers comprises electrospinning a dispersion and collecting a plurality of electrospun fibers, followed by submerging the collected fibers in a coagulation bath.

This invention pertains to a novel process for preparing fibers from poly(α(1→3) glucan). The fibers prepared according to the invention, have“cotton-like” properties, are useful in textile applications, and can be produced as continuous filaments on a year-round basis. The process comprises solution spinning from a novel solution of poly(α(1→3) glucan) in a mixture of water and N-methylmorpholine-N-oxide followed by coagulation in a liquid coagulant that comprises a liquid that is not water.

The present invention discloses a method for preparing hemp viscose fiber by using hemp plant and hemp visose fiber prepared by adopting said method. Said method includes the following steps: preparing raw material, digesting, washing material, pulping, removing sand, bleaching, water-washing, fiber-making, impregnating, pressing, pulverizing, aging, xanthating, dissolving, mixing, filtering, defoaming, spinning, drawing, cutting and making after-treatment.

The invention relates to water-soluble polymer/graphene composite fiber as well as a preparation method and application thereof. The cross section of the fiber is special-shaped, the surface of the fiber is of an orientated micro-fiber-shaped structure, the strength of the fiber is greater than 100 MPa, the elongation at break is greater than 2%, and the conductivity of the fiber is greater than 0.1 S/cm. The preparation method comprises the following steps: preparing a composite spinning liquid, extruding into a coagulating bath for curing, drafting, leading out of the coagulating bath, drying, and coiling, thereby obtaining the water-soluble polymer/graphene composite fiber; and finally reducing by using a chemical or physical method, thereby obtaining the water-soluble polymer/graphene composite fiber. The cross section of the composite fiber provided by the invention is of a special-shaped structure, the surface of the fiber is of a rich groove micro structure, the strength and the toughness of the fiber are greatly improved when being compared with those of pure graphene fiber, and good conductivity is still maintained, so that the water-soluble polymer/graphene composite fiber has a wide application prospect in the fields such as anti-electrostatic and conductive fabrics, electromagnetic wave absorption and shielding fabrics, energy storage devices, sensors and water treatment.

The invention discloses a biomimetic preparation method of a high-strength regenerated silk protein fiber. The method takes high crystallization degree, high strength, high modulus nano cellulose whiskers with a large length-diameter ratio to simulate the beta-fold microcrystal in the natural silk fiber, then mixes the nano cellulose whiskers with a regenerated silk fibroin solution, and finally prepares the high-strength regenerated silk protein fiber through a wet spinning method. The characteristic that a large amount of hydroxyl groups in the molecular chains of the rigid nano cellulose whiskers can form intermolecular hydrogen bonds with polar groups such as carboxyl groups, amino groups, and the like, in the molecular chains of silk protein is utilized to achieve the structural bionics of the regenerated silk protein fiber, and thus improves the mechanical properties of the regenerated silk protein fiber. The preparation method is simple, and does not pollute the environment. The mechanical properties of the obtained regenerated silk fiber are equal to or even better than those of natural silk, and the regenerated silk fiber has the similar micro-structure and configuration as the natural silk.

Solutions formed by combining poly(α(1→3) glucan) with CS₂ in aqueous alkali metal hydroxide solution have been shown to produce the xanthated form of the poly(+(1→3) glucan). The solutions so formed have been shown to be useful for solution spinning into fiber of poly(α(1→3) glucan) when the spun fiber is coagulated in an acidic coagulation bath. The fibers so produced exhibit desirable physical properties. The poly(α(1→3) glucan) employed was synthesized by fermentation.

The invention relates to a method for preparing graphene/polyimide composite fibers. The method comprises the following steps of: (1) preparing graphene or graphene oxide; (2) preparing a graphene/polyamic acid spinning solution; and (3) preparing graphene/polyimide or graphene oxide/polyimide composite fibers. According to the method, through adopting stripped graphene layers as addition materials of polyimide fibers, the spinnability of the polyamic acid spinning solution is improved, the stability of the polyamic acid fibers is improved, the improvement on the performance of the fibers is facilitated, and thus, the polyimide fibers with excellent performance are prepared; and with the adoption of the method, the problem of difficulty in the spinning and the forming of the polyamic acid fibers is solved, the mechanical properties of the composite fibers is improved, meanwhile, the problems of uneven dispersion and interfacial adhesiveness of the graphene in a matrix polymer are solved.

Disclosed herein are a polyimide dope solution composition, a method for preparing a hollow fiber using the composition and a hollow fiber prepared by the method. More specifically, disclosed are a method for preparing a hollow fiber, comprising preparing a polyimide dope solution composition comprising polyhydroxyimide, polythiolimide or polyaminoimide, spinning the composition to prepare a hollow fiber, and thermally rearranging the hollow fiber, and the hollow fiber prepared by the method.

In accordance with the method, a hollow fiber made of a high free volume polymer membrane can be prepared by spinning the dope solution composition to prepare a hollow fiber and thermally rearranging the hollow fiber via thermal treatment. The hollow fiber thus prepared exhibits excellent gas permeability and selectivity, thus being suitable for use as a gas separation membrane.

The invention relates to a hollow or solid fibre having multiple porous layers concentrically arranged, and wherein at least one of the layers comprises functionalized or active particles that are well accessible and maintain their function after preparation. The layer containing high loads of particles can be either the outer or the inner layer. The main function of the other porous layer is to provide mechanical stability to the fibre. It can further act as a sieve and prevent unwanted compounds or species to come in contact with the functionalized particulate matter. Where it is the inner layer, the second layer can advantageously be a biocompatible material. With the second being the outer layer it is now possible to reach a particle content of 100 wt % in the inner layer. These fibres comprising high densities of functionalized particulate matter and of still sufficient mechanical strength can be used for (selective) adsorption, conversion, isolation or purification of compounds from a mixture of compounds, in particular from a fermentation broth, tissue broth, plant broth, cell broth or blood.

The invention discloses a method for preparing chitosan fibers, which comprises the following steps: mixing 2.0 to 6.0 weight percent of chitosan, 4.0 to 6.0 weight percent of lithium hydroxide, 0.5 to 4.0 weight percent of urea, 0.1 to 3.0 weight percent of glycerol and the balance of water, and swelling to prepare chitosan spinning solution; and spinning by a wet-process spinning method, coagulating and precipitating in a coagulating bath to form protofilaments, washing, drawing, and drying to obtain the chitosan fibers. In the invention, the spinning solution is prepared by dissolving chitosan in an alkaline solvent, the chitosan macromolecular chains exist in a high-swelling state, the arrangement of the chitosan macromolecular chains is more compact, the high instability of the chitosan in acidic solution is overcome, the hydrolysis of the chitosan macromolecular chains and the breakage of the glucosidic bonds are avoided, the oriented arrangement of the macromolecular chains is promoted, and the mechanical properties of the chitosan fibers are improved.

The present invention relates to high strength carbon fibers having structured surface grooves, and a preparation method thereof. According to the present invention, a wet spinning technology is adopted, and a solvent adopted by polymerization and solidification molding is modified, such that the solvent and the modifying agent form a complex structure so as to improve solidification double-diffusion in the wet spinning solidification molding process to prepare a polyacrylonitrile precursor having a axial structured surface groove structure and a uniform and dense radial structure; and then pre-oxidation structure control is adopted in a pre-oxidation process to prepare the high strength polyacrylonitrile-base carbon fibers having the structured surface groove structure. The carbon fibers of the present invention have high tensile strength and high modulus, and are easily compounded with other materials so as to improve performances of the composite material.

The invention relates to a method for preparing a high polymerization degree bacterial cellulose fiber. The method comprises the following steps: (1) dissolving the bacterial cellulose in solvent to prepare bacterial cellulose solution with mass fraction of 1-30 percent, filtering and standing the solution for deaeration, thus obtaining spinning solution; (2) forming the spinning solution in the step (1) by solidifying after the solution is sprayed through a spinneret orifice, and preparing a finished product after several conventional processes, such as stretching, washing, shaping and drying. The preparation method is simple and is applicable to industrial production; compared with other cellulose fibers, the bacterial cellulose fiber has high rupture strength and module reaching the level of high-tensile industrial yarn, and has the advantages of good biocompatibility, odegradability, hydrophilicity and binding property with rubber.

The invention discloses a preparation method for composite carbon fiber based on graphene/ polyacrylonitrile. The preparation method comprises the following steps: adding 0.01-10 parts by weight of initiating agent under nitrogen protection into 1 part by weight of graphene or oxidized graphene, 10-1000 parts by weight of solvent and 10-1000 parts by weight of acrylonitrile monomer; heating to 50-95DEG C; reacting for 1-60 hours; precipitating, carrying out centrifugation, washing and drying to obtain the polyacrylonitrile grafted graphene; dispersing the polyacrylonitrile grafted graphene into polar organic solvent to obtain spinning solution sol; continuously extruding the spinning solution from a spinning head capillary at a constant speed to enter solidification solution; collecting the solidified primary fiber; and drying to obtain the graphene fiber primary silk; and carrying out chemical or thermal treatment to obtain the graphene/ polyacrylonitrile composite carbon fiber. The preparation method is simple and convenient, has simple technology, is convenient and quick for post-processing, and can be produced on a large scale. The obtained graphene/ polyacrylonitrile composite carbon fiber embodies excellent intensity, toughness, modulus thermal stability and electrical conductivity and can be applied in various industrial fields to replace the traditional carbon fiber.

The invention discloses a preparation method of halogen-free flame retardant high-intensity polyvinyl alcohol fibers, which is characterized by comprising the following steps of uniformly mixing 20-45 parts by weight of phosphate ester flame retardant powder with the average particle size no more than 1.0 microns, 1-10 parts by weight of dispersing agent, and 40-79 parts by weight of water to prepare flame retardant suspended slurry, continuously mixing the slurry and polyvinyl alcohol plus boron spinning solution with the polymerization degree of 1700-3000 and the alcoholysis degree more than 99 percent through a mode of spun injection, carrying out spinning with the mixed solution through a polyvinyl alcohol wet method plus a spinning process route, carrying out neutralization, wet-heat drawing, washing and drying on solidified fibers to obtain as-spun fibers, preheating the as-spun fibers to the temperature of 200-230 DEG C, drawing by 2-4 times, and then carrying out heat setting on the fibers at the temperature of 180-210 DEG C for 2-5min to obtain the halogen-free flame retardant high-intensity polyvinyl alcohol fibers. According to different uses, post-treatment steps such as formalization, oiling, curling, cutting and the like can be selectively carried out on the flame-retardant fibers. The flame-retardant fibers prepared through the method has the advantages of low toxicity and high intensity, realizes self-extinguishment after leaving fire, is free of halogen and the dripping phenomenon and is used for aspects of fabric flame retarding, enhancing flame retardant fabrics and the like, and the limited oxygen index can reach 28-30.

The invention discloses a method for producing melamine formaldehyde resin/polyvinyl alcohol flameproof fiber. The invention is characterized in that composing melamine and formaldehyde at the mole ratio as 1:1.2-1:6 and 50-100Deg. C into melamine formaldehyde resin water solution, to be mixed with the polyvinyl alcohol water solution at the solid content ratio as 2:8-8:2 to obtain spinning original liquid, then spinning and shaping the original liquid via general wet method, and treating solidifying bath via acid sodium sulfate saturated water solution, and the primary fiber is drawn, shaped via wet and heat method, washed, coiled, oiled, dried, and heated in dry condition to obtain the final melamine formaldehyde resin/polyvinyl alcohol flameproof fiber. The titer of said flameproof fiber is 10detex, while the strength is 1-3cN/dtex, the crack extended rate is 5-15%, the regain ratio is 5-10%, and the limit oxygen index is 30-45.

The invention relates to a viscose staple fiber with high white strength and fine denier and a production process thereof, which belong to the viscose staple fiber and the production method of the textile spinning industry and the non-woven fabric industry. Its raw materials and weight percent content are: 86.7-92 percent of cellulose fiber, 7.7-13 percent of water, and 0.15-0.30 percent of oil agent. The raw materials are impregnated, squeezed, yellowed, spun, drawn, bundled, scoured, bleached twice with hydrogen peroxide, and dried to make finished products. The product of the present invention has finer denier, higher strength, higher yarn count and higher strength, and the garment fabric has higher strength, strong abrasion resistance, delicate hand feeling, wrinkle resistance and resistance to multiple deformations than ordinary viscose of the same process. Short fiber processing clothing fabrics and other advantages. High-count yarn products have thinner fabrics and lower grammage. The area of ​​fabrics processed from raw materials of the same weight is increased and the cost is reduced.

An electrospinning apparatus including a spinning dope main tank, a metering pump, a nozzle block, a collector positioned at the lower end of the nozzle block for collecting spun fibers, a voltage generator, a plurality of units for transmitting a voltage generated by the voltage generator to the nozzle block and the collector, said electrospinning apparatus containing

• • a spinning dope drop device positioned between the metering pump and the nozzle block, the spinning dope drove device having
  • (i) a sealed cylindrical shape,
  • (ii) a spinning dope inducing tube and a gas inletting tube for receiving gas through its lower end and having its gas inletting part connected to a filter aligned side-by-side at the upper portion of the spinning dope drop device,
  • (iii) a spinning dope discharge tube extending from the lower portion of the spinning dope drop device and
  • (iv) a hollow unit for dropping the spinning dope from the spinning dope inducing tube formed at the middle portion of the spinning dope drop device.

The invention relates to a process for preparing carbon nano-tube/ polyimide compound fiber, which comprises the steps that: (1) the carbon nano-tube happens ultrasound in concentrated nitric acid and concentrated sulfuric acid, happens a reflux reaction and is cooled, washed and dried in a water bath, the carbon nano-tube which is acidulated and isocyanate are acted at room temperature through ultrasound, washing and drying. (2) Damine monomer is added into organic solvent and is mechanically stirred until being completely dissolved, equimolar dianhydride monomers are added in batches and are stirred in water bath, and polyamide acid solution is obtained. (3) The carbon nano-tube which is functionalized by the isocyanate is added into the polyamide acid solution to do the wet spinning, and then the carbon nano-tube/polyimide compound fiber which is made through the processes of amination and stretching. The invention has the advantages of simple preparation technology, low cost and no environmental pollution.

The invention relates to a method for preparing high-performance polyacrylonitrile-based carbon fiber protofilament through dry spraying and wet spinning, which comprises the following steps: preparing a polyacrylonitrile spinning stock solution; filtering and metering the polyacrylonitrile spinning stock solution after the demonomerization and deaeration; squeezing obtained materials through a spinning jet for forming fine spinning streams for entering a coagulating bath for coagulating forming through an air section; and carrying out drafting, water washing, drying densification, steam drafting and drying hot forming to obtain the high-performance polyacrylonitrile-based carbon fiber. The fiber firstly passes through a section of air layer, and then enters the coagulating bath for spinning forming by a wet method. The fine streams of the spinning solution is in a cylindrical shape after leaving spinneret orifices under the action of the gas-liquid interface tension, a primary cuticular layer is formed, and the cuticular structure is smooth. The method has the advantages of simple process, easy control and relatively low cost. In addition, the method also has the advantages that the spinning speed is high, the production efficiency can be improved, in addition, the surface of the obtained protofilament is smooth, the residual quantity of the solvents is greatly reduced, the quality homogenization degree of the protofilament is improved, and the mechanical property is excellent.

The invention provides a production process of wool protein compound viscose fiber, which belongs to the technical field of viscose fiber. The process comprises the steps of preparing a wool protein spinning solution, blending the wool protein spinning solution with a viscose spinning solution, spinning, solidifying and curing and performing aftertreatment to obtain the wool protein compound viscose fiber. In the invention, the addition of toxic substances is avoided, the obtained finished product is more suitable for manufacturing the textile products with high safety, such as intimate apparels and the like, and shows the advantages in environmental friendliness.

Methods are provided according to aspects of the present invention for making starch fiber or particle compositions by wet-electrospinning or wet-electrospraying including providing a solution or dispersion of starch in an aqueous or non-aqueous solvent or dispersant, where the starch is present at a concentration above the critical entanglement concentration, with the proviso that the aqueous or non-aqueous solvent or dispersant does not consist only of water; heating the solution or dispersion of starch to a temperature above the crystallization temperature of the starch; electro spinning or electro spraying the heated solution or dispersion of starch to produce starch fibers or starch particles, respectively; and contacting the starch fibers or starch particles with a coagulation bath fluid.

The invention discloses a high-conductivity graphene fiber and a preparation method thereof. By the adoption of the wet spinning technology, oxidized graphene spinning liquid with the mass percentage being 1-10% is extruded from a spinning head into a coagulating bath to obtain an oxidized graphene gel fiber, the oxidized graphene gel fiber is collected on a graphite rolling shaft after being fully solidified, the oxidized graphene fiber is obtained, and the oxidized graphene fiber is sequentially subjected to chemical reduction, high-temperature thermal treatment and chemical doping. The prepared graphene fiber has high conductivity, and the conductivity of the prepared graphene fiber is one magnitude order higher than that of a common graphene fiber. The whole process is simple and controllable in technology, and conductivity of the graphene fiber is improved. The obtained graphene fiber has excellent mechanical property and excellent electrical conductivity and thermal conductivity. The high-conductivity graphene fiber can be used for preparing soft solar batteries, supercapacitors and wearable devices and can serve as a light wire to be used in ultra-light wires and cables, and it is hopeful to replace a metal copper wire with the graphene fiber for new-generation power transmission.

The invention relates to a preparing method for SiO2/cellulose tough aerogel fibers. The preparing method comprises the steps that silicate or silanol sol is prepared into a spinning solution, a cellulose solution is added, then the mixture is injected into an H2SO4/Na2SO4 solution for a reaction for wet method spinning, and orthosilicic acid/silicate/cellulose fibers are obtained; the fibers are wound and steeped into an H2SO4/Na2SO4 solution for aging at the room temperature, the fibers are washed with deionized water to be neutral, solvent replacement is carried out, the fibers are dried, and the SiO2/cellulose tough aerogel fibers are obtained. The method has the advantages that raw materials are cheap and easy to obtain, the reaction process is simple, and spinnability is good. The prepared continuous SiO2/cellulose tough aerogel fibers contain abundant holes, have a high specific surface area and are resistant to high temperatures and chemical corrosion; meanwhile, the fibers are adjustable in specific surface area and have certain toughness, the application range of the aerogel fibers can be enlarged, and higher practical value is achieved.

The invention relates to a polyacrylonitrile-based hollow carbon fiber precursor and a preparation method thereof. The polyacrylonitrile-based hollow carbon fiber precursor of the invention can be used for preparing polyacrylonitrile-based hollow carbon fibers. An acrylonitrile binary copolymerization system containing itaconic acid or an acrylonitrile ternary polymerization system containing itaconic acid and methyl acrylate is adopted for spinning by a wet spinning process matched with a circular arc slit spinneret plate, and multiple filament bundles of the hollow carbon fiber precursor can be obtained, wherein the dimension of the outer diameter and the structure of the precursor meet the requirement of a conventional preoxidation carburizing process for precursor fibers, and the groove structure on the surface of the fiber is favorable for improving the interface performance of composite materials.