104results about "Dry spinning methods" patented technology

The invention provides a dyeable high-temperature-resistant modified meta-position aramid fiber and a preparation method thereof. The modified meta-aramid fiber is mainly prepared from a spinning solution prepared from m-phenylenediamine, methyl 3, 5-diaminobenzoate, 3, 3 '-diaminodiphenyl sulfone and an isophthaloyl dichloride copolymer through dry spinning, and the dye uptake of a disperse dye is not lower than 85%; the thermal decomposition temperature is not less than 400 DEG C. The preparation method comprises the following steps. S1, fully continuous polymerization; s2, continuously neutralizing and conveying; s3, direct spinning; and S4, fiber forming and post-treatment. The method has the advantages that (1) the quality difference between batches in the traditional intermittent method is eliminated, and the uniformity and stability of the product performance are realized; and the preparation process is compact, the production efficiency is high and the energy consumption is low. And (2) the dyeing performance of the prepared fiber is obviously improved, the inherent high-temperature-resistant characteristic of the aramid fiber is maintained, and the mechanical property is excellent. And (3) the application range of the meta-position aramid fiber is expanded.

The application discloses a method for preparing silicon carbide ceramic fibers by combining sol-gel and dry spinning. The method comprises the following steps: 1) after preparing a second silicon-based sol, a spinning aid is added to prepare a spinnable silicon-based sol; 2) the spinnable silicon-based sol is prepared into fiber filaments by using a dry spinning process; 3) the fiber filaments are cracked into silicon-carbon-oxygen fibers; and 4) the silicon-carbon-oxygen fibers are sintered into silicon carbide ceramic fibers. The method is different from a mainstream polycarbosilane precursor method for preparing silicon carbide ceramic fibers, does not need a non-melting treatment process, has the advantages of adjustable composition, low raw material cost and simple process and the like, and has important significance for low-cost preparation of silicon carbide ceramic fibers.

Mechanically and piezoelectrically anisotropic polymer fibers may be formed by spinning a polymer solution or gel that includes a high molecular weight crystallizable polymer and a liquid solvent. The solvent may be configured to interact with the polymer to facilitate chain alignment and, in some examples, create a higher crystalline content within the spun fibers. The polymer solution may also include a low molecular weight additive. The high and low molecular weight polymers may each be characterized by a bimodal molecular weight distribution where the molecular weight of the additive is less than the molecular weight of the crystallizable polymer. The polymer(s) and the additive(s) may be independently selected from vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropene, vinyl fluoride, etc. The spun fibers may be oriented, annealed, poled, and woven or laminated to form a polymer thin film having a high elastic modulus and a high electromechanical coupling factor.

A method of integrated and improved one-step production of carbon fiber precursors is described, in particular from comonomer start up until the spinning step to obtain the final fiber precursor.

This invention provides a method for producing nanofibers that does not use highly toxic crosslinking agents and has a low environmental impact. Furthermore, it also provides a method for producing food freshness sensors and drug-supported nanofibers based on the nanofiber production method of this invention. [Solution] A method for producing nanofibers, comprising: a spinning solution preparation step of preparing a spinning solution containing a citrus-derived material obtained from citrus fruits and a water-soluble polymer that can be made into fibers; a nanofiber formation step of forming nanofibers from the spinning solution by electrospinning; and a crosslinking step of crosslinking the nanofibers.

A process for preparing a carbon fiber precursor wherein the precursor is selected from a series of solid PAN (polyacrylonitrile) fibers, wherein each member of the series contains about 2 weight % to about 8 weight % completely neutralized itaconic acid.

To provide an electrostretching machine with improved material uniformity. [Solution] The present invention relates to an electrostretching machine with improved material uniformity, in which the shape of the electric field generated between the emitter and the collector is changed stably or variably over time, thereby achieving a more uniform deposition of fiber-particles. To do this, the machine comprises a steering electrode (6) positioned at the end of an injector (1), the steering electrode (6) being connected to a power module (5) that applies a potential difference to the steering electrode to exert a repulsive or attractive force on the fiber-particles (4), and a collector (3) comprising conductive material regions (8) positioned on the surface of an insulating material (7) that are electrically insulated from each other, and a voltage which can have a continuous or alternating amplitude and / or phase is applied to the conductive material regions (8).

The application is a preparation method of polylactic acid-based polyurethane elastic fiber, comprising the following steps: step 1, reacting polylactic acid polyol, isocyanate compound and catalyst to obtain isocyanate group terminated prepolymer; step 2, fully reacting the prepolymer, chain extender and capping agent in the presence of a solvent in a reactor to obtain a polyurethane solution; step 3, using the polyurethane solution as a spinning solution to obtain polylactic acid-based polyurethane elastic fiber by dry spinning. The added nucleating agent and heat treatment technology are used to form a more perfect crystalline structure in the fiber, and the crystals act as physical crosslinking points, so that the fiber has higher modulus and breaking strength. The polylactic acid polyol with biodegradability is used to replace the traditional polymer polyol to synthesize polyurethane fiber, so that the prepared spandex is degradable, and the problems of difficult degradation and environmental pollution of waste spandex are effectively solved.

The present invention refers to a method and device for the preparation of microfibres and nanofibres based on hyaluronic acid and / or a water-soluble metal or non-metal salt thereof or a mixture of salts and / or a derivative of hyaluronic acid by method of dry spinning, and two-dimensional or three-dimensional fibrous materials from this microfibres and nanofibres. The resulting 2D or 3D materials can be for example in the shape of layer or cotton wool. Furthermore, the present invention refers to a device for performing this method, that contains an extrusion part containing a pass-through channel, that has an inlet opening for feeding the spinning solution and a dispensing opening for dispensing the spinning solution and furthermore the device contains an air nozzle, the air outlet opening of which is arranged to direct the exiting air into the area surrounding the dispensing opening of the extrusion part parallel to the axis of the dispensing opening of the extrusion part.

According to the present disclosure there is provided a method of depositing a fibre onto a freestanding object using a fibre deposition apparatus. The fibre deposition apparatus comprises a dispenser and a moveable arm defining a deposition zone. The method comprises: positioning the fibre deposition apparatus such that the freestanding object is located within the deposition zone, forming a droplet of a fibre-forming liquid composition at an outlet of the dispenser, moving the arm from a first position in contact with the droplet to a second position away from the first position so as to draw the droplet into a drawn fibre, and depositing the drawn fibre onto the freestanding object as the arm moves from the first position to the second position. According to a further aspect of the present disclosure there is provided a fibre deposition apparatus for depositing fibres onto a freestanding object. According to a further aspect of the present disclosure there is provided a liquid composition for forming a drawn fibre. The liquid composition comprises a fibre-forming polymer; a solvent; and a functional component.

Expanded polytetrafluoroethylene (ePTFE) monofilaments with superior knot pull tensile strength are described herein, which can be used as sutures and in medical devices such as for tethers and anchors for cardiac repair. The properties of these monofilaments balance the need for an inert, soft, lubricious and porous material with sufficient tensile properties for high strength applications.

A purpose of the present invention is to provide a crosslinked-gelatin nanofiber filter which has satisfactory flexibility, is less apt to break when in use, and can have controlled solubility under specific temperature conditions. The crosslinked-gelatin nanofiber filter comprises gelatin, a thickening polysaccharide, and a cyclic sugar, does not dissolve in 20°C pure water, has a dissolution time in 25°C pure water of 60 minutes or shorter, and has an average fiber diameter of 300-600 nm.

The application provides a kind of bio-based spandex elastic fiber and its preparation method, the bio-based spandex is introduced into spandex molecular chain by bio-based polyether polyol, and the bio-based polyether polyol contains bio-based 1,3-propanediol unit structure.The preparation method is that the bio-based spandex is obtained by including bio-based polyurethane prepolymer, mixed amine reaction to obtain the raw material containing polyurethane-urea polymer, and the raw material is used as the spinning solution to obtain by dry spinning.The performance of the spandex product is close to the petrochemical-based spandex product, which can perfectly replace the petrochemical-based spandex product and better promote the transformation and upgrading of the product.The technical problem that the difference in performance between bio-based raw materials and petrochemical-based materials leads to insufficient reaction or instability is solved, the conventional petroleum-based spandex production equipment can be directly used, and industrial production is realized.

The present invention provides a fiberization apparatus and a dry film formation apparatus that avoid damage and aggregation of material particles and improve the uniformity of particle size after pre-fiberization. [Solution] The fiberization apparatus includes a fiberization mechanism 100, a feeding mechanism 200, and a cutting and sorting mechanism 300. The fiberization mechanism includes two fiberization rollers 101 arranged opposite each other, with a supply gap 102 formed between the two fiberization rollers, and the supply gap includes a supply end and a discharge end. The feeding mechanism is located above the supply end. The cutting and sorting mechanism is located below the discharge end and includes a hopper 301, a crushing member 302, and a screen 303, the screen being located below the crushing member. A constant pressing and shearing force is applied to the material fed into the supply gap via the opposing fiberization rollers, so that the material is fiberized without being subjected to strong impact, the material can be effectively fiberized, and damage to the material particles due to strong impact can be avoided.

The application provides a shaped cross-section carbon fiber precursor, a shaped cross-section carbon fiber and a preparation method, and relates to the technical field of carbon fibers. The preparation method of the shaped cross-section carbon fiber precursor comprises the following steps: extruding a spinning dope through a spinneret with a shaped hole according to a preset spinning rate to form a dope fine stream; making the dope fine stream pass through an air layer with a preset height and then enter a coagulation bath to be coagulated and formed at a first preset temperature to obtain a nascent fiber; and performing post-treatment on the nascent fiber to obtain the shaped cross-section carbon fiber precursor. The shaped degree of the spinneret with the shaped hole is 0.2-0.8. The preset spinning rate is 15.00-25.00 m / min. The preset height is 1.5-4.5 mm. The concentration of the coagulation bath is 30-70 wt%. The first preset temperature is 5-55 DEG C. The shaped cross-section carbon fiber prepared from the polyacrylonitrile-based precursor according to the application has the characteristics of high specific surface area, high compactness and low skin-core ratio.

The invention provides an agar hydrogel fiber preparation device and method based on micro-fluidic heat exchange. The agar hydrogel fiber preparation device comprises a coaxial micro-fluidic heat exchange unit, a supply heat preservation unit, a cooling unit and a collection unit. According to the invention, the outer side sleeve is coaxially sleeved outside the inner capillary tube to form the coaxial micro-fluidic heat exchange unit with the annular cooling channel, so that a cooling medium flowing in the cooling channel can perform efficient radial heat exchange with an agar-based solution flowing through the inner capillary tube through the tube wall; therefore, the problems of low heat exchange efficiency, non-uniformity and the like caused by dependence on air or substrate cooling in a traditional preparation method are effectively solved. The efficient heat exchange mechanism ensures that the agar-based solution can be quickly and uniformly cooled below a gel point within an extremely short time of flowing through the inner capillary tube, and high-speed continuous and stable forming of the fiber is realized.

A preparation method of an aerogel fiber and use are provided. The preparation method includes: mixing a solvent and a polymer material to form a spinning solution; driving the spinning solution with a high-speed airflow by using a blow spinning technology to form a jet flow, and forming a gel fiber through sol-gel transition; and performing solvent replacement on the gel fiber and then performing drying treatment to prepare the aerogel fiber. The method for preparing the aerogel fiber through blow spinning has no high requirements on a gelation process of an aerogel material, and can achieve the preparation of the aerogel fiber by using this method after the spinning solution meeting rheological conditions is obtained, thereby avoiding the influence of the inadequate gelation process on fiber properties while promoting the production efficiency of the aerogel fiber and greatly simplifying procedures.

The invention discloses a tank truck rear anti-collision beam and bumper composite material and a preparation method thereof, and belongs to the technical field of composite materials. The material comprises an upper surface layer, a middle layer and a lower surface layer, the upper surface layer and the lower surface layer are blended felts of modified polyimide fibers and high-strength and high-modulus fibers, and the middle layer is a mixed curing material of the modified polyimide fibers and resin. The modified polyimide fiber is subjected to copolymerization modification by introducing a diamine monomer containing a benzothiazole group and a sulfuryl group, so that the heat resistance, flame retardance and mechanical stability of the fiber are remarkably improved. During preparation, the modified polyimide fiber is cleaned, blended and calendered to obtain the surface layer, then the surface layer and the resin are mixed and pre-pressed to obtain the middle layer, and finally the three layers are compounded into a whole through pultrusion. The prepared composite material has excellent high-temperature resistance, impact resistance and flame retardance, meanwhile, light weight is achieved, the safety of a tank truck in a rear-end collision accident can be effectively improved, the service life is prolonged, and the maintenance cost is reduced.

The application belongs to the field of functional polymer materials, and particularly relates to a preparation method of a high-toughness hydrophobic fiber membrane without the action of an electric field force. An ultrahigh molecular weight polymer prepared by room temperature emulsion polymerization is fully dissolved in a high-boiling-point polar solvent, and a high-toughness polymer fiber membrane with good hydrophobicity is obtained by using a microfluidic nanogas jet spinning technology. The preparation method is simple to operate, does not need a static electric field, has strong controllability, good spinnability, can be tractionally stretched, can orderly form a film through a chemical reaction, has fast surface drying, and is low in energy consumption.

A high population density of closed C shaped cellulose acetate filament can now be reliably produced. The closed C filaments are made from a spinneret having a. substantially D shaped orifice under particular processing conditions depending on the dpf of the filament, the theta angle of the D shaped orifice, and dope temperature. The process can make a high population count of closed C shaped fibers in a. tow band, and article are not provided having the high population density of closed C shaped fibers.

The invention discloses a spinning control method and a related device. The target fineness and the current torque of a target fiber are obtained. According to the target fineness, the target torque of the target fiber is determined, and when the drawing roller for producing the target fiber is the target torque, the target fiber meets the quality condition. If the difference between the current torque and the target torque is larger than a first difference threshold value, reducing the difference between the current torque and the target torque serves as an adjusting target, and target torque influence factors are adjusted and comprise at least one of the cooling air temperature, the glue solution composition or the glue solution temperature. Therefore, the tension for producing the target fiber is reflected through the current torque, so that the target torque influence factors can be directly adjusted, and the fiber tension can be maintained in a normal interval more timely. In addition, compared with the uncertainty of adjusting the process based on a finished product inspection result after production, the adjustment mode based on the torque difference can be quantified and has higher certainty, and the accuracy of process adjustment is improved.

To provide a method for producing hyaluronate-containing fine fibers that are excellent in moisture retention and hygroscopicity and contain high-molecular-weight hyaluronate at a high concentration, hyaluronate-containing fine fibers, and a textile product.SOLUTION: A method for producing hyaluronate-containing fine fibers comprises: a step of preparing a mixed aqueous solution containing a hyaluronate having a weight average molecular weight of 500,000 or more, a polymer having a hydrophilic group and water; and an electro-spinning of injecting the mixed aqueous solution charged from a spinning nozzle on which a high voltage is applied to spin hyaluronate-containing fine fibers. The hyaluronate-containing fine fibers contain a hyaluronate having a weight average molecular weight of 500,000 or more and a polymer having a hydrophilic group, and the hyaluronate is contained in an amount of 10 mass% or more based on a total amount of the fibers.SELECTED DRAWING: Figure 1

This invention provides an online testing device and method for carbon fiber precursor oiling agents based on a dry-jet wet spinning process, belonging to the field of carbon fiber precursor production technology. The testing device includes an oiling tank for holding a first oiling agent solution and an oiling agent testing component located at the top of the oiling tank. The oiling agent testing component includes a testing oiling tank for holding a second oiling agent solution. The carbon fiber precursor includes a first filament and a second filament. The first filament can be drawn in and out of the oiling tank to complete the oiling treatment with the first oiling agent solution, and the second filament can be drawn in and out of the testing oiling tank to complete the oiling treatment with the second oiling agent solution. By placing the oiling agent testing component at the top of the oiling tank, this invention ensures that the spacing between various process components in a conventional carbon fiber production line is within a reasonable range, facilitating maintenance and inspection of relevant components by operators, ensuring sufficient operating space, and reducing safety risks.

To enable electret effects given to a fiber to be maintained for an extended period.SOLUTION: A fiber includes a fine fiber including a first phase and a second phase. The first phase includes a first polymer which is a paraelectric material and the second phase includes a second polymer which is other than the paraelectric material, and at least a part of the second phase is included in the first phase.SELECTED DRAWING: Figure 1

The invention relates to a polyamide-imide fiber and a preparation method and application thereof, based on rapid reaction of isocyanate and trimellitic anhydride monomers under the action of an organic weak base catalyst, an amine monomer containing disulfide bonds is added, rapid synthesis of a high-solid-content polyamide-imide spinning solution is realized through a microreactor, and the polyamide-imide fiber is prepared. And directly conveying to a dry spinning system to prepare the disulfide bond-based polyamide-imide fiber with the self-repairing characteristic. The problems of low preparation efficiency, high cost and the like of a traditional batch-type process are avoided, continuous synthesis of the microreactor is beneficial to preparation of high-molecular-weight polyamide-imide fibers, and the polyamide-imide fibers have excellent mechanical properties.

The present invention relates to a process for producing a polymeric material comprising: (i) at least one organic solvent; (ii) (A) at least one organopolysiloxane compound containing a group having an aliphatic carbon-carbon multiple bond; (B) at least one organopolysiloxane compound having a Si-bonded hydrogen atom, or instead of or in addition to (A) and (B), (C) at least one organopolysiloxane compound containing a Si-C bonded group having a group with an aliphatic carbon-carbon multiple bond and a Si-bonded hydrogen atom; (However, all of the above (A), (B) and (C) are performed at 25°C for 0.1 seconds.) -1 The viscosity measured at a shear rate of 800,000 mPa·s or less. (D) at least one hydrosilylation catalyst; (E) no filler or at least one silicone-containing filler; an addition-crosslinking silicone elastomer comprising (iii) 25°C, 0.1 s -1 at least one polysiloxane other than (A), (B), (C), and (E), having a viscosity of more than 5,000,000 mPa·s measured at a shear rate of Electrospinning solution comprising:

This invention relates to the field of spinning machine technology and proposes a high-viscosity dosing solution modular continuous filament spinning machine, comprising a connecting pipe and a spinneret forming mechanism arranged sequentially. The connecting pipe has a plurality of liquid outlets, and the spinneret forming mechanism has a plurality of units connected to the plurality of liquid outlets. The connecting pipe includes a liquid inlet pipe; a plurality of first pipes and second pipes, each having a plurality of units, one first pipe connected to two second pipes, and one second pipe connected to two first pipes, with the first and second pipes spaced apart; the liquid inlet pipe is connected to one of the first pipes or one of the second pipes; and a plurality of riser pipes, each connected to one of the first or second pipes at the end, with an angle between the riser pipe and both the first and second pipes, and each riser pipe having one liquid outlet. This technical solution solves the problem of poor yarn quality in existing filament spinning devices during mass production.

A process of producing cellulose ester fibers in a retrofitted elastane production facility is provided, the process comprising: a. providing an elastane production facility comprising an elastane polymerizing zone, an elastane mixing zone, an elastane spinning zone, and an elastane spinning cabinet zone; b. converting the elastane production facility to a retrofitted elastane production facility to produce cellulose ester fibers; wherein the retrofitted elastane production facility comprises a cellulose ester mixing zone, a cellulose ester fiber spinning zone, and a cellulose ester fiber spinning cabinet zone; optionally wherein the elastane polymerizing zone is not utilized in the retrofitted elastane production facility; c. producing the cellulose ester fibers in the retrofitted elastane production facility.

Described are precursor fibers of lignin-based carbon fibers with a content of water-soluble lignin salt (A). A special characteristic of these precursor fibers is the inclusion of water-soluble polyvinylpyrrolidone or a derivative (B) thereof. Further described is an advantageous process for producing these precursor fibers as well as their advantageous use for producing carbon fibers by carbonization, optionally followed by graphitization.

The invention discloses a continuous spinning process for preparing high-uniformity aramid fiber, which relates to the technical field of spinning processing and comprises the following steps: stock solution preparation and defoaming, metering and conveying, extrusion and forming, graded solidification, hot stretching and online detection and winding. The three-stage gradient coagulating bath is used for simulating fiber skin-core layer slow phase separation, a countercurrent circulation system is matched for maintaining the concentration and temperature stability of bath liquid of each layer, air layer micro-airflow disturbance inhibits solvent volatilization difference, the structure unevenness caused by too fast traditional coagulating surface is avoided, skin-core defects and surface wrinkles are reduced, and meanwhile, the surface quality is improved. An on-line detection system integrating laser scanning, infrared spectroscopy and tension sensing is used for monitoring the fiber state in real time, rapidly feeding back signals and dynamically adjusting coagulating bath, stretching and winding parameters, closed-loop control is formed, process fluctuation is restrained, consistency in batches is improved, and the rejection rate is reduced.