412results about "Spinning head liquid feeder" patented technology

The invention provides a superfine denier profiled polyester staple fiber and a preparation method thereof.The preparation method includes the steps of raw material pretreatment, melt spinning, nascent filament treatment, heat setting and curling, oiling and cutting off and the like, polyester chips have high intrinsic viscosity and melting point, and under the action of six-zone temperature control, a high-hole-density spinneret plate and a high draft multiple, the polyester chips are subjected to melt spinning, so that the polyester chips are prepared into the superfine denier profiled polyester staple fiber. The superfine, special-shaped and hollow polyester staple fibers are prepared. The obtained polyester staple fiber has good breaking strength, rebound resilience and a low-defect structure, the bulkiness, flexibility and structural consistency of the fiber are remarkably improved, the environment and process limitation of a traditional sea-island fiber alkali stripping method is broken through, and the polyester staple fiber is suitable for the fields of high-end filling, plush imitation, non-woven materials and the like.

The invention discloses a moisture-absorbing and sweat-guiding polyester fabric and a preparation method thereof, and relates to the technical field of high-performance fiber fabrics. The invention discloses a moisture-absorbing and sweat-guiding polyester fabric which comprises moisture-absorbing and sweat-guiding polyester fibers. The moisture-absorbing and sweat-guiding polyester fiber contains 5-12wt% of cool-feeling particles; the preparation method comprises the following steps: firstly, depositing mesoporous silica on the surface of a base material by using a pretreated mica sheet to obtain modified particles; coating the modified particles with a binary phase change material to obtain core-shell particles; and finally, carrying out hydrophilic treatment on the surfaces of the core-shell particles to obtain the cool-feeling particles. The cool particles are added into polyester, so that the polyester material is endowed with instantaneous cool performance, and the polyester is endowed with moisture absorption and sweat guide performance. The polyester fabric prepared by weaving the moisture-absorbing and sweat-guiding polyester fibers has good wearability.

The invention relates to the technical field of high polymer material processing, and discloses an efficient polyester fiber continuous production method based on multi-screw cooperation, which comprises the following steps: S1, raw material pretreatment and conveying: carrying out multi-stage filtration on a polyester raw material, and simultaneously directly conveying supercritical fluid to a feed port of a multi-screw extruder through a closed pipeline; s2, adding a catalyst: adding an organic metal complex catalyst before the polyester raw material enters a reaction extrusion stage; s3, carrying out multi-screw synergistic reaction; s4, data acquisition and analysis; s5, performing dynamic adjustment and feedback; s6, separating and recycling; and S7, spinning and post-processing. Through cooperation of multiple screws and the supercritical fluid and the catalyst, impurities in the raw materials can be dissolved, the activation energy of the reaction can be reduced, the purity of the raw materials can be improved, the viscosity of the materials can be reduced, the flowability is improved, uniform mixing of the raw materials and the catalyst is promoted, the reaction activity is remarkably enhanced, and a foundation is laid for subsequent efficient polymerization reaction; the quality and the production efficiency of the polyester fibers are improved.

The utility model relates to the technical field of chemical fiber production, in particular to a melt cooling device of a direct spinning melt conveying system, a melt cooler is arranged on a conveying pipeline in the direct spinning melt conveying system, the melt cooling device further comprises an ethylene glycol evaporator of a polyester device, and a heating medium pipeline and a refrigerant pipeline are arranged on the ethylene glycol evaporator. The refrigerant pipeline and the heating medium pipeline are connected to the melt coolers, a heating medium pump is arranged on the heating medium pipeline, the heating medium pipeline is connected to the refrigerant pipeline corresponding to each melt cooler through an adjusting pipeline, and an adjusting valve group is arranged at the joint of the adjusting pipeline and the refrigerant pipeline and used for adjusting the temperature of a refrigerant medium. The cooling medium generated by the ethylene glycol evaporator of the polyester device is used for cooling the melt in the melt cooler, and the heating medium generated by the melt cooler is used for heating the ethylene glycol evaporator, so that the full utilization of energy is realized, the energy consumption waste is reduced, and the equipment cost and the production cost are reduced.

The invention relates to the technical field of control systems, in particular to a high-strength polyethylene fiber melt flow control system and method. Comprising a melt conveying unit, a pressure adjusting unit, a temperature control unit, a flow monitoring unit and a central control unit, the melt conveying unit is used for conveying high-strength polyethylene fiber melt; the pressure adjusting unit is arranged in a pipeline of the melt conveying unit and used for adjusting melt conveying pressure. The temperature control unit is used for controlling the temperature in the melt conveying process; the flow monitoring unit is arranged at the tail end of the melt conveying unit and used for monitoring the melt flow in real time; the central control unit is electrically connected with the pressure adjusting unit, the temperature control unit and the flow monitoring unit, receives monitoring data of the flow monitoring unit and conducts coordinated regulation and control on the pressure and temperature of the melt through the pressure adjusting unit and the temperature control unit according to preset flow parameters. The flow of the high-strength polyethylene fiber melt is accurately controlled.

The invention relates to the technical field of spinning preparation, and discloses cool color master batch gradient blended spinning and a preparation method thereof.The preparation method comprises the steps that the proportion of cool master batches and color master batches is obtained, and the cool master batches and the color master batches are prepared; the preparation method comprises the following steps: performing nano coating treatment on a cool master batch and a color master batch to obtain an optimal synergistic ratio of the cool master batch and the color master batch, dynamically adjusting a blending ratio and a process path, performing programming regulation and control on a cool degree and color shade to execute a partitioned melting and mixing strategy, and performing staged functional component mixing; a gradient color distribution strategy is executed, material distribution in the fibers is adjusted, annular airflow is adopted for cooling, the cooling speed and the cooling flow direction are controlled, and the melt is rapidly shaped; comparing the actual parameters of the generated fiber structure with the target performance demand parameters, and judging whether the color distribution uniformity, the cool feeling performance index and the structural integrity meet preset standards or not; according to the scheme, the diversified requirements of the market for cool feeling and color can be better met.

The invention belongs to the technical field of polyester fiber spinning, and discloses a polyester fiber spinning device and a processing method thereof.The polyester fiber spinning device comprises a shell, a metering pump fixed to the top of the shell and an air cooling heat dissipation part located at the bottom of the shell, a conveying assembly is fixedly connected to the interior of the shell in a sleeved mode, and the bottom of the conveying assembly fixedly communicates with a distribution assembly. Staggering is completed by means of left-right deflection of the upper-layer spinning assembly and the lower-layer spinning assembly, after moving and staggering are conducted through a first adaptation groove and a second adaptation groove in the spinning assemblies, the first adaptation groove is aligned and communicated with the lower hole, the second adaptation groove is aligned and communicated with the upper hole, and flushing water guided into the first adaptation groove and the second adaptation groove is utilized for flushing the upper hole and the lower hole. According to the spinneret assembly, flushing and cleaning from inside to outside are carried out towards the spray holes in the upper side and the lower side in an isolated mode along the interior of the spinneret assembly, on one hand, blocking objects in the spray holes are cut off when the deflected lower half spinneret plate rotates, on the other hand, a flushing mode from inside to outside exists, and the final flushing effect is improved.

The invention discloses a differential shrinkage mixed fiber polyester one-step processing technology, which comprises the following steps: after final shrinkage molding of a PET polyester melt through a polyester final shrinkage kettle, injecting the PET polyester melt into a spinning manifold through a melt filter, a booster pump, a melt conveying pipeline, a cooler and a static mixer in sequence; after being distributed, melts in the spinning box body are respectively shunted into a first metering pump and a second metering pump to be injected into corresponding spinning assemblies for feeding; after one half of the spinning assembly discharges filaments, POY tows are obtained through circular blowing cooling and oil nozzle oiling, the other half of the tows enter IBox five hot rollers through a GR0 draw-off godet to be stretched to form FDY tows, and the FDY tows and the POY tows enter a pre-network at the same time to be subjected to network fiber mixing to form preformed ITY tows; and then sequentially entering a GR2 draw-off godet, a main network and a GR3 draw-off godet, carrying out full-automatic integrated winding and doffing to form ITY tows, and finally carrying out quality inspection, packaging and warehousing. The method has the remarkable advantages of being short in technological process, low in energy consumption, high in production efficiency, uniform and stable in quality and high in additional value, and the differential shrinkage rate can be flexibly adjusted.

The invention relates to the technical field of fibers, in particular to durable antibacterial polyamide composite fibers and a processing technology thereof.The composite fibers comprise, by weight, 70%-90% of polyamide base materials, 5%-20% of antibacterial agents and 2%-5% of dispersing agents, according to the durable antibacterial polyamide composite fiber, the silver zeolite antibacterial agent is adopted, the content of silver ions is appropriate, the silver ions are distributed in a gradient mode, long-acting antibacterial performance is guaranteed, the silver zeolite antibacterial agent is evenly dispersed in the fiber and regularly arranged in a three-dimensional space, the consistency of different positions is high, bacteria are effectively inhibited, and the durability of the antibacterial polyamide composite fiber is improved. The nylon antibacterial fiber is suitable for antibacterial textiles, antibacterial agent distribution of the fiber is stable, antibacterial uniformity and durability are guaranteed due to the radial and length direction characteristics, meanwhile, the molecular weight and molecular chain structure of the nylon base material provide a good strength and toughness basis for the fiber, the length and distribution of the fiber are reasonable, the shape of the cross section is regular, and stress is uniform when the fiber is stressed.

The invention belongs to the field of high-performance materials, and discloses a high-thermal-conductivity PBO fiber and a preparation method thereof, and the preparation method comprises the following steps: (1) preparing a PBO polymer solution with a conventional molecular weight; (2) preparing an ultra-high molecular weight PBO polymer solution; (3) mixing the two PBO polymer solutions in a double-screw extruder according to a certain proportion to obtain a PBO spinning solution; (4) preparing as-spun PBO fibers by adopting a dry-wet liquid crystal spinning process and a condensed state structure regulation and control means; and (5) washing, drying, oiling and winding the as-spun PBO fiber to obtain the high-thermal-conductivity PBO fiber. According to the method, a small amount of the ultra-high molecular weight PBO polymer is added into the conventional spinning solution, the heat conduction performance of the PBO fiber is remarkably improved through the induced orientation crystallization effect of an ultra-high molecular weight PBO long chain, and the method has good application prospects in the field of high-power radio frequency microwave circuits with high requirements for heat dissipation capacity.

The invention discloses an integrated rheology detection and automatic control method and device. The method comprises the following steps: S1, acquiring a viscosity detection value of slurry; s2, the viscosity detection value of the slurry is compared with a viscosity set value, if the viscosity difference value exceeds a set range, the viscosity is dynamically adjusted through a pre-established logic control model, and the logic control model is used for adjusting the viscosity difference value within the set range by adjusting model factors related to the viscosity; the model factors include a temperature factor and a pressure factor associated with viscosity. The temperature, the pressure and the rotating speed are dynamically adjusted through the logic control model, so that the viscosity is adjusted; through multi-parameter cooperative control, the rheological fluctuation amplitude of the slurry can be greatly reduced, the consistency of the slurry is improved, and the spinning spinnability and the strength uniformity of tows are improved.

The utility model discloses composite simulated fur fiber spinning equipment, and relates to the field of polyester filament yarn production.According to the composite simulated fur fiber spinning equipment, a first raw material is metered into a first raw material and a second raw material with different deniers through two metering pumps in a feeding mechanism, the first raw material enters a first cavity through a pipeline and then is sprayed out through a first spinning part at the bottom of the first cavity, and the second raw material enters a second cavity through a pipeline; a second raw material enters a second cavity through the other pipeline and then is sprayed out through a second spinning part at the bottom of the second cavity, meanwhile, a second raw material is sprayed out through the other feeding mechanism, and due to the fact that the component sections of the first spinning part and the second spinning part are different, the denier sections of the sprayed first raw material and the second raw material are different. According to the utility model, two different denier cross sections can be sprayed in one material distributing assembly, so that the technical problem that the existing fiber manufacturing equipment cannot manufacture various different denier cross section fibers in the production process at the same time is solved, and the technical effect that the various different denier cross section fibers can be manufactured in the production process at the same time is achieved.

The utility model belongs to the technical field of spinning, and discloses a spinning device based on liquid crystal polyarylate fibers, which comprises a support base, a screw conveyor positioned in the middle of the support base, and a mixing structure positioned above the screw conveyor, the mixing structure comprises two mounting frames mounted outside the screw conveyor, a stirring barrel mounted at the tops of the two mounting frames and a servo motor located below the stirring barrel, the mixing structure is matched with the screw conveyor, liquid crystal polyarylester fibers and corresponding additives are placed in the stirring barrel, and the liquid crystal polyarylester fibers and the corresponding additives are uniformly mixed. And then the servo motor is started to drive the meshing wheel A tightly connected with the servo motor to quickly and stably rotate, meanwhile, the meshing wheel A drives the meshing wheel B and the meshing wheel C to rotate, and in the high-speed rotation process of the meshing wheel A and the meshing wheel C, the outer rod and the inner rod which are connected with the meshing wheel A and the meshing wheel C can present the coaxial reverse rotation effect, so that strong and complex shearing force is generated.

The utility model discloses a melt filtering device meeting double-screw feeding, and relates to the technical field of non-woven fabrics, the melt filtering device meeting the double-screw feeding comprises a filter main body, one side of the filter main body is provided with two melt inlet and outlet seats, and the two melt inlet and outlet seats are arranged on the other side of the filter main body. Discharging switching valves are arranged at the front end and the rear end, close to the top end, of the melt inlet and outlet seat, and feeding switching valves are arranged at the front end and the rear end, close to the bottom end, of the melt inlet and outlet seat. The problems that in the prior art, part of slices in a large drying tower need to be blown to a small drying tower for secondary drying and heat preservation, then melt conveying is conducted through a small screw extruder and a small filter, the distance between the large melt filter and the small melt filter is long, temperature control cannot be completely consistent, and electric energy and heat energy losses are large are solved.

A meltblown system includes a die including a die inlet end to receive molten polymer from a polymer source, a cavity located downstream from the die inlet end through which the molten polymer flows, and a die outlet end to receive the molten polymer from the cavity and deliver to outlet orifices at the die outlet end. A fluid supply includes a channel that delivers fluid to the die outlet end to attenuate fibers formed from molten polymer emerging from the die outlet end. The fluid supply provides fluid at a temperature T2 that differs from a temperature T1 of the molten polymer within the cavity, and the meltblown system is configured to independently maintain the molten polymer within the cavity at the temperature T1 during operation of the meltblown system.

Disclosed is a fiber forming device, which is highly suitable for producing a nonwoven web with excellent barrier properties. In one aspect, the fiber forming device can be used to produce a meltblown web or a co-formed web. The fiber forming device includes a die having multiple rows of polymer nozzles for forming fibers. An air flow path is positioned on either side of the multiple rows of polymer nozzles. Additionally, the air flow path is positioned between the multiple rows of polymer nozzles. The air flow path produces a refined air flow, which refines the fibers produced by the polymer nozzles and guides the fibers onto a forming surface for forming a nonwoven web.

The utility model relates to the technical field of coating mechanisms, in particular to a supply coating mechanism of a nanofiber electrostatic spinning machine, which comprises a plurality of metering pumps, a plurality of liquid inlet pipes and an adjusting rotating mechanism, and the adjusting rotating mechanism comprises a rotating column, a rotating frame, a driving assembly, a plurality of coating blocks, a plurality of coating pipes, a plurality of dismounting assemblies and an auxiliary assembly. The rotating column and the driving assembly are installed in the electrostatic spinning machine, the number of the coating blocks is selected according to needs, the rotating frame is inserted, the multiple electrostatic spinning pieces are embedded into the multiple coating grooves respectively, the driving assembly is fixed and started through the multiple disassembling and assembling assemblies respectively, and under cooperation of the auxiliary assembly, the rotating frame rotates with the rotating column as a rotating shaft; the multiple coating blocks are driven to rotate, the multiple metering pumps are started, and polymer solutions are injected into the multiple coating grooves through the multiple liquid inlet pipes and the multiple coating pipes correspondingly, so that supply coating is conducted on multiple pieces of electrostatic spinning, and the effect of improving the adaptability of the mechanism is achieved.

The utility model discloses a spinning box for monofilament production, which comprises a box shell, a distribution mechanism, a plurality of spinning units and a heating medium mechanism, wherein a heating cavity is formed in the box shell, and the distribution mechanism, the spinning units and the heating medium mechanism are mounted on the box shell. The distribution mechanism comprises a total distribution head and a plurality of metering components which are mounted on the box shell, and a plurality of distribution passages which are communicated between the total distribution head and the plurality of metering components; the total distribution head is configured to uniformly distribute a melt extruded by the extrusion equipment to the plurality of metering components through the plurality of distribution passages; the plurality of spinning units are in one-to-one correspondence with the plurality of metering components, each spinning unit comprises a plurality of spinning ports for outputting the melt, and each metering component is configured to uniformly distribute the melt conveyed by the distribution passage to the plurality of spinning ports; the heating medium mechanism comprises a heating medium inlet pipe and a heating medium return pipe which are communicated with the heating cavity, and a plurality of electric heating rods arranged on the box shell in a penetrating manner; the multi-head filament spraying device can uniformly spray filaments in a multi-head mode and is suitable for production of monofilaments of different varieties.

The invention discloses a preparation method of ultra-high molecular weight polyethylene fiber, fiber and spinning equipment, and the preparation method comprises the following steps: (1) mixing ultra-high molecular weight polyethylene powder with a solvent, uniformly swelling, and feeding into a twin-screw extruder for fully dissolving to obtain a spinning solution; spraying the spinning solution through a spinneret plate, drafting in an air gap, and cooling in a cooling bath to obtain gel silk; (2) carrying out shrinkage balance on the gel silk; then carrying out pre-extraction and pre-drying to obtain gel filaments with low solvent concentration, and storing the gel filaments in a filament containing barrel for later use; and (3) sequentially carrying out multi-stage extraction, drying, multi-stage drafting and winding on the jelly silk with low solvent concentration to obtain the ultra-high molecular weight polyethylene fiber. Through the steps of shrinkage balance, pre-extraction and drying treatment on the gel silk, adverse effects caused by solvent precipitation and gel silk shrinkage in the standing process of the gel silk can be reduced, the fiber fineness can be controlled to be stable and uniform, the production process is short, the occupied area of equipment is small, and the investment is low.

An object of the present invention is to improve the efficiency in transferring heat from a heated box to a spinning pack, regardless of the size of a gap between the heated box and the spinning pack. A melt spinning device 1 includes: a cylindrical spinning pack 2 including a spinneret 21; a heated box 3 including a concave portion 32 having the internal space into which the spinning pack 2 is inserted; and a heat-transmission mechanism 4 which is positioned at a gap between the wall surface defining the concave portion 32 and the surface of the spinning pack 2 when the spinning pack 2 is inserted into the concave portion 32. The concave portion 32 is open downward. The heat-transmission mechanism 4 includes plate springs 41 in each of which the shape is elastically valuable in accordance with the size of the gap. When the spinning pack 2 is inserted into the concave portion 32, each plate spring 41 forms a heat conduction path which reaches the surface of the spinning pack 2 from the wall surface defining the concave portion 32 in the heated box 3.

The present application relates to the technical field of composite hollow fiber production control, in particular to a three-component composite hollow fiber low-resistance high-efficiency spinning system and control method, comprising the following steps: setting the target pressure value of each component; the core control unit delivers three-component melt to the composite spinning box; the pressure sensing module collects the instantaneous pressure value of the three melts at the spinneret inlet in real time; calculating the independent deviation of the instantaneous pressure value of each component melt from the target pressure value; calculating the difference between the instantaneous pressure values of the three-component melts, and identifying the maximum pressure difference; comparing the maximum pressure difference with the maximum pressure deviation threshold; superimposing the independent rotation speed compensation signal on the initial rotation speed setting value of each servo driver to adjust the rotation speed of each extrusion mechanism screw in real time. The present application effectively eliminates the problem of pressure mismatch caused by temperature fluctuations, screw disturbance or material viscosity changes.

Materials are provided that can be used for electromagnetic interference (EMI) shielding, and methods of fabricating the same and methods of using the same are also provided. Polymer-based fiber thin films can have superior electrical conductivity and excellent EMI shielding efficiency while being ultra-flexible and ultra-lightweight. The fiber thin films can be dual polymer thin films and can incorporate quantum dots (QDs) (e.g., magnetic quantum dots) and / or two-dimensional (2D) conductive nanomaterials within a dual polymer matrix comprising a conductive polymer and a nonconductive polymer. The resultant composite thin film can have low density, high porosity, and high electrical conductivity.

Compact module for wet spinning of chemical fibres of the type comprising a spinning head (F) of 2-8 tows (S), each one consisting of a plurality of continuous filaments, relative supply pumps (P) of the spinning solution, a coagulation tank (V) containing a coagulation solution, and a plurality of drive rollers (2) and respective idle diverter rollers (3) which determine a zigzag path of the tows (S) downstream of the spinning area, in the rectilinear lengths of which liquid-based treatments are carried out on said tows (S). The rectilinear lengths of said zigzag path are horizontal and said liquid-based treatments on the tows (S) are carried out in horizontal treatment trays (4) of the spillway type.

The invention relates to a method for producing spunbonded fabric (1), wherein a spinning material (2) is extruded through a plurality of nozzle holes (4) of at least one spinneret (3, 40, 50) in order to form filaments (5), and each of the filaments (5) is stretched in the extrusion direction, wherein the filaments (5) are laid on a perforated conveyor device (10) in order to form a spunbonded fabric (1), and the nozzle holes (4) of the spinneret (3, 40, 50) are arranged along a main axis (6) aligned in the transverse direction (12) relative to the conveyor direction (11) of the conveyor device (10) such that the spunbonded fabric (1) formed on the conveyor device (10) is stretched in said transverse direction (12). The aim of the invention is to allow a reliable adjustment of the spinning width and the weight distribution per surface unit of the spunbonded fabric or allow the weight distribution per surface unit to be kept constant during an ongoing operation using said method. This is achieved in that the spinning material throughput (31) of the nozzle holes (4) is variably set along the transverse direction (12).

The invention provides a spinning device. The spinning device comprises a feeding port, a screw extrusion assembly, a spinning box, a detachable temperature control assembly, a bearing plate and a winding assembly. The screw extrusion assembly is connected with the feeding port. The spinning box body is connected with the screw extrusion assembly. The detachable temperature control assembly is arranged below the spinning manifold body, and the ratio of the length of the spinning manifold body to the length of the detachable temperature control assembly is 1: 1-2.5. The bearing plate is fixed to one end of the spinning manifold and located between the spinning manifold and the detachable temperature control assembly. The winding assembly is coupled with the detachable temperature control assembly. According to the spinning device, production of the thermoplastic liquid crystal polymer fibers can be achieved more easily, the spinnability is improved, and the quality of the generated thermoplastic liquid crystal polymer fibers can also be improved.

The resin composition for melt spinning of the present invention is a filament having a melt viscosity of 250 Pa·s or less at 200° C. and a shear rate of 0.1 s−1 and a tensile strength of 10 MPa or more. The filament can be produced by forming a molten liquid of a resin composition having a melt viscosity of 250 Pa·s or less at 200° C. and a shear rate of 0.1 s−1 into a filament shape to provide a formed material, and conveying and concurrently cooling the formed material. The present invention also provides a resin composition for melt spinning being a filament, and a method for producing fiber using a melt spinning apparatus.

The present disclosure relates to a center fluid distributor for a multi-fiber spinneret for producing hollow fiber membranes in a phase inversion process.

The present invention relates to an air-permeable stretchable circuit, which can be activated by stamping, preparation method and use thereof, belonging to the field of flexible electronic technology. The preparation method includes steps of: dissolving a thermoplastic polymer in a solvent, then adding liquid metal particles and mixing to obtain a mixed solution; performing electrospinning on the mixed solution to prepare a nanofiber membrane; performing stamping on the nanofiber membrane with a stamping mould having a circuit pattern, to obtain the air-permeable stretchable circuit. The invention ensures air-permeability and stretchability through using nanofiber membranes. Due to the matching diameters of the liquid metal particles and the fibers, stamping can cause the liquid metal inside the nanofibers to overflow and form conductive paths, thereby achieving high-precision preparation of circuits.

The lightweight melt-blown hot-melt nonwoven fabric containing hydrophobic nanosilica according to the manufacturing method of the present invention performs an adhesive function when interposed between adherends such as fabric, even if a smaller amount of adhesive resin is applied than a conventional hot-melt film, it has the effect of saving material costs and energy by about 10 to 50% while ensuring uniformity of adhesive strength for each section, excellent peel strength, and good breathability. As a result, fabric products using the melt-blown hot-melt nonwoven fabric can prevent overflow during the adhesion process and achieve lightness and a soft texture.

Certain aspects of the disclosure concern a device including a nozzle configured to receive a heated polymer solution from a reservoir and a power supply configured to generate an electrostatic field between a tip portion of the nozzle and a substrate so as to draw a charged jet of the heated polymer solution out of the tip portion of the nozzle toward a substrate situated at an operating distance from the tip portion of the nozzle and form a polymer fiber on the substrate. The heated polymer solution is at an operating temperature that is greater than or equal to 40° C.