CN108360103B

CN108360103B - Spinning process and spinning device for micro-nanofiber covered yarns

Info

Publication number: CN108360103B
Application number: CN201810408251.1A
Authority: CN
Inventors: 刘梅城; 洪杰
Original assignee: Nantong Textile Vocational Technology College
Current assignee: Hongwei Yancheng Textile Co ltd
Priority date: 2018-05-02
Filing date: 2018-05-02
Publication date: 2021-01-26
Anticipated expiration: 2038-05-02
Also published as: CN108360103A

Abstract

The invention discloses a micro-nanofiber covered yarn spinning process and a spinning device, wherein the spinning device comprises a device body, a V-shaped cavity is arranged in the device body, a mandrel for accommodating core yarn to enter is arranged at the upper part of the V-shaped cavity, a melt-blowing nozzle for accommodating micro-nanofibers to penetrate into is arranged at the side part of the device body, a plurality of compressed air inlets are further arranged at the side part of the device body, the compressed air inlets are communicated with the V-shaped cavity, and a yarn guide roller, a bobbin yarn and a winding roller are sequentially arranged below a discharge outlet at the bottom of the V-shaped cavity. According to the micro-nanofiber air-jet spinning device, the micro-nanofibers perform spiral motion in the V-shaped cavity, complete stretching and twisting along with traction and rotation of the rapid air flow, and then are wound on the core yarn to form the core-spun yarn, so that the produced yarn is fluffy in structure and multiple in pores, and has the functions of antibiosis, heat insulation, warm keeping, filtering, adsorption, sound absorption and the like.

Description

Spinning process and spinning device for micro-nanofiber covered yarns

Technical Field

The invention belongs to the technical field of spinning, and particularly relates to a spinning process and a spinning device for micro-nanofiber covered yarns.

Background

The melt-blown spinning technology is mainly used for producing non-woven fabrics. Melt-blown nonwoven technology originated in the early 50's of the 20 th century, when the U.S. naval laboratory, with government support, was developed and developed for the collection of radioactive particles in the upper atmosphere following a nuclear bomb explosion, by extruding molten polymer through an extruder into a converging stream of hot air, and blowing the resulting superfine fibers toward a coalescer under the stretching action of the air stream, thereby accumulating a superfine filter. This process is a prototype of modern melt blown nonwoven technology. In the middle of the 20 th century and the 60 th century, the method was improved by the American Exxon company, the technology was converted into civil use in the 70 th century, a non-woven material development and development center is established in association with the American Tianna university, and the melt-blown technology enters the research and development stage of obstetrics and universities. Beginning in the 80 th 20 th century, melt-blown nonwoven materials have been growing rapidly worldwide, maintaining an annual growth rate of 10-12%, and have been developed dramatically.

The melt-blown nonwoven fabric was first developed in the united states in the 50 s of the 20 th century, and was developed in the early 60 s in China. It is a high and new technology product, which is directly spun into cloth by polypropylene chips with high melt index.

The melt-blown non-woven process flow comprises the following steps: the polymer chips are heated and melted in a screw extruder, the melt is conveyed into a spinneret orifice of a spinneret plate, the polymer melt leaving the spinneret orifice forms superfine filaments or superfine short fibers under the strong drafting action of high-speed high-temperature air flow, and the superfine filaments or the superfine short fibers are deposited on a net forming curtain or a receiving roller along with the air flow to form a melt-blown fiber net.

The melt-blown technology is a processing technology that after polymer melt is extruded from a die head, the polymer melt is acted by high-speed hot air flow, before the polymer jet is cooled and solidified, the polymer jet is stretched by the high-speed air flow, and superfine fiber non-woven fabrics are directly formed on a receiving device.

The diameter of the commercial melt-blown fiber is usually 1-10 μm, and the minimum diameter of the melt-blown fiber which can be prepared by using the melt-blown technology in the laboratory at present is less than 0.6 μm, which belongs to nano-fiber. And extruding the mixture from a spinneret plate, entering a high-speed high-temperature airflow field, and rapidly stretching and thinning the mixture to micro-nano fibers.

The fiber of the melt-blown non-woven fabric is characterized by being superfine, the minimum fiber diameter can reach 0.5 mu m, generally between 1 and 5 mu m, the thinner the fiber is, the better the quality of the non-woven fabric is, but the yield is relatively reduced.

The diameter of the melt-blown fiber is very small, the specific surface area is large, the pore size of the fiber web is small, and the melt-blown non-woven product has excellent particle interception, particle capture performance and heat retention. At the same time, meltblown products also have unusual capillary action and breathability (water is impermeable to blood and water vapor permeable). For this reason, the melt-blown products are also widely used as filter materials, thermal materials, sanitary materials, medical materials, and the like.

The polymer is fed from a feeding hopper, is pushed to the front of a machine barrel by a screw extrusion thread driven by a screw motor to rotate, and passes through 5 heating areas with different temperatures in sequence. The temperature of the polymer in the machine barrel can be gradually increased, the physical state of the polymer is also changed into a high elastic state from a glass state, and finally the polymer becomes a viscous state to be completely melted. The screw rotates steadily at a certain speed to deliver the homogeneous molten polymer isobarically and equivalently to the spinneret. And (3) extruding polymer fine flow after flowing through the pore diameter of the spinneret plate, drafting and melting the polymer by two high-temperature high-speed air flows to prepare the micro-nano fiber.

The CQ-M81-PP nano polypropylene slice has the functions of transparency, heat insulation, sound absorption and the like, and is a PP polypropylene slice rich in a novel superfine composite nano material.

The polyimide fiber has the characteristics of high and low temperature resistance, flame retardance, no molten drop, self-extinguishing after being away from fire and excellent heat insulation, and the heat-insulation protective clothing made of the polyimide fiber is comfortable to wear, good in skin adaptability, permanently flame retardant, stable in size, good in safety and long in service life. The material is also an excellent thermal insulation material due to low thermal conductivity coefficient of the material.

The long staple cotton has good quality, longer fiber, generally 33-39 mm, higher strength, soft fiber, good moisture absorption and air permeability. The cotton fiber is internally provided with a middle cavity structure, so that the heat retention is good.

The siro compact spinning is characterized in that two pieces of rough yarn are parallelly fed into the same drafting mechanism of a ring spinning machine at a certain interval, are simultaneously drafted in a parallel state, form two fiber bundles with a certain interval after coming out from a clamping point of a front roller, pass through a group of gathering elements at the position of a spinning triangular area of the front roller, enable two loose fiber strands drafted to be tightly embraced together by the air guiding function when respectively passing through the surface of a negative pressure suction gathering pipe, and are output by a guiding rubber roll and gathered together by twisting action to be twisted into yarn. The siro compact spun yarn has a structure similar to a plied yarn, and the surface fiber of the yarn is orderly arranged, has high strength, good wear resistance and little filoplume and has smooth appearance.

CQ-M81-PP nano polypropylene chips are melt-blown and spun into fibers, and the fibers are wound on the surface of the long stapled cotton/polyimide fiber blended yarn in the spinning process through the spinning device, so that the yarn and the fabric have better heat insulation and warm keeping effects.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to solve the defects in the prior art and provides a spinning process and a spinning device for micro-nanofiber covered yarns.

The technical scheme is as follows: the invention relates to a spinning process of micro-nanofiber covered yarns, which comprises the following steps:

(1) preparing a core yarn;

(2) passing the core yarn through an air jet spinning device, and simultaneously coating the micro-nano fibers sprayed out by a hot melting nozzle on the surface of the core yarn to form a coated yarn by using an air jet principle;

(3) finally, the yarn is led out by a yarn leading roller and is wound into a cone yarn by a yarn guiding roller and a winding roller.

Further, the core yarn in the step (1) adopts compact spinning polyimide and long staple cotton combed blended yarn, and the mixing ratio of the combed long staple cotton to the polyimide is as follows: 20-80%: 80-20%, and the specific process comprises the following steps:

BC262 type wool making machine → FB220 type semi-worsted spinning carding machine → two-channel FA311F type drawing frame → FA458 type roving frame → EJM128A type spinning frame → 1332MD type winder;

pretreating polyimide fibers: after opening the polyimide fiber, preparing spinning oil according to 5 percent of the weight of the raw materials, spraying the spinning oil into the fiber, and covering the fiber for 24 hours by using a plastic film; the preparation method of the spinning oil agent comprises the following steps: adding the softening agent into water according to the ratio of 1:5, stirring to form a uniform aqueous solution, adding an antistatic agent accounting for 20% of the weight of the aqueous solution, and stirring uniformly, wherein the softening agent is a UC-588-227 polyester softening agent;

long stapled cotton: processing long stapled cotton through blowing-carding combination to form cotton slivers, performing combing pre-drawing, sliver doubling and rolling to form small rolls, processing the small rolls through a combing machine to form combed slivers, and controlling the doffing rate of the combing machine to be between 11 and 14 percent;

tearing off the combed strips, and mixing the combed strips with the treated polyimide fibers in a wool blending machine according to the weight percentage;

(1) semi-worsted carding machine: preparing a cotton sliver by performing wool blending and cotton carding on polyimide fibers and long stapled cotton combed cotton fibers, wherein the cotton sliver ration is controlled to be 18.5-23 g/5 m;

(2) drawing: carrying out secondary doubling on cotton slivers obtained by carding, wherein the ration of the cotton slivers obtained by the secondary doubling is controlled to be 17.5-23 g/5 m;

(3) roving: controlling the back draft multiple of the roving frame to be 1.35 times, controlling the roving twist coefficient to be 60-90, and then carrying out roving treatment;

(4) spinning: spinning the spun yarn by adopting a siro compact spinning mode to obtain a siro compact spinning polyimide and long stapled cotton combed blended yarn;

(5) spooling: the speed of the bobbin winder is controlled at 500-700m/min, and the bobbin winder adopts an electronic yarn cleaner and an air splicer to form a cone yarn.

Further, the air-jet principle and process in the step (2) are as follows: at the upper end of the V-shaped air-jet spinning tube, high-speed hot air is sprayed into the spinning tube along the tangential direction, and rotates in the V-shaped cavity under the constraint of the spiral guide plate, and the micro-nano fibers are sprayed out by the hot melting nozzle and are continuously pulled, rotated and stretched under the guidance of hot air flow rotating at high speed; the four compressed air jet holes are distributed along the tangential direction, and the injected compressed air rotationally accelerates and cools the rotating hot air flow from the upper part of the V-shaped cavity, so that the micro-nano fibers are crystallized and formed during cooling; the diameter of the V-shaped spinning tube is smaller and smaller along with the downward movement of the airflow, the rotating speed is accelerated continuously, the micro-nano fibers are further stretched and twisted under the guidance of the high-speed rotating airflow, the lower part of the V-shaped cavity is provided with a pressure reducing exhaust hole, and the high-speed rotating airflow is exhausted through the exhaust hole.

Further, the micro-nano fiber in the step (2) adopts CQ-M81-PP nano polypropylene slices.

Further, step (2) air-jet spinning device includes the device body, this internal V-arrangement that is equipped with of device holds the chamber, V-arrangement holds chamber upper portion and is equipped with the dabber that holds the core yarn and get into, the lateral part of device body is equipped with the mouth that melts that holds the entering of micro-nanofiber, the lateral part of device body melts the nozzle both sides and is equipped with hot-air inlet, hot-air inlet and V-arrangement hold the chamber and is linked together, the middle part of device body still is equipped with a plurality of compressed air inlets, compressed air inlet and V-arrangement hold the chamber and is linked together, the lower part of device body still is equipped with a plurality of decompression exhaust holes, V-arrangement holds chamber bottom discharge gate below and is equipped with in proper order and draws yarn roller, leads yarn roller, section of.

Further, the radius of the V-shaped cavity is gradually reduced from top to bottom.

Further, the mandrel and the discharge hole at the bottom of the V-shaped cavity are coaxial.

Furthermore, the upper part of the melting nozzle is provided with a hot air inlet, and the lower part of the melting nozzle is provided with four symmetrical compressed air inlets.

Furthermore, a spiral guide plate is arranged below the melting nozzle.

Further, the angle a of the V-shaped cavity ranges from 5 degrees to 60 degrees.

Has the advantages that: according to the micro-nanofiber covered yarn spinning process and the spinning device, the micro-nanofiber is drawn and twisted along with the drawing and rotation of the rapid airflow by making spiral motion in the V-shaped cavity, and then the micro-nanofiber is wound on the core wire to form the core-spun yarn, so that the bonding rate is high, the working efficiency is high, and the produced yarn has the functions of antibiosis, heat insulation, warm keeping, filtration adsorption, sound absorption and the like. Because the core yarn is not twisted any more, and the micro-nanofibers are wrapped on the core yarn through rotating and winding, the formed wrapping yarn can not generate the torsional stress similar to that of ring spun yarn, the wrapping is uniform, and the bonding rate is high.

The invention provides a melt-blown micro-nano one-step spinning device, and by the device, micro-nano fibers formed by melt-blowing are twisted by spiral airflow and directly coated on core yarns to form coated yarns, so that great progress is brought to the melt-blown micro-nano fiber spinning technology, and a wide space is provided for the application of the micro-nano fibers. The device has compact structure and reasonable design, is convenient for industrialized and large-scale production, combines spinning and cladding into yarn, greatly shortens the process flow, and is beneficial to the technical progress of the textile industry.

The micro-nanofiber covered yarn produced by the device has the performance of micro-nanofibers and the structure of the covered yarn, provides more choices for the development of micro-nanofiber yarn products, and enlarges the market space of micro-nanofibers.

Drawings

FIG. 1 is a schematic diagram of a micro-nanofiber fusion process according to the present invention;

FIG. 2 is a schematic illustration of the core yarn fusing process of the present invention;

FIG. 3 is a schematic sectional view of the upper portion of the V-shaped chamber of the present invention;

FIG. 4 is a schematic cross-sectional view of the middle of a V-shaped chamber of the present invention.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the following specific examples.

The invention relates to a spinning process of micro-nanofiber covered yarns, which comprises the following steps:

(1) preparing a core yarn;

Further, the core yarn in the step (1) adopts compact spinning polyimide and long staple cotton combed blended yarn, and the mixing ratio of the combed long staple cotton to the polyimide is as follows: 20-80%: 80 to 20 percent. The specific process comprises the following steps:

Wherein, the grade of the long stapled cotton is 137, and the specification of the polyimide fiber is 1.6dtex 38 mm. Long stapled cotton: blowing and carding, wherein the cotton sliver ration is 21.3g/5 m; combing: the quantitative determination was 23.5g/5 m.

Polyimide fiber is called PI fiber for short, and is an important high-performance fiber variety. The polyimide fiber has the advantages of obvious high-strength and high-modulus characteristics due to the fact that the density of aromatic rings in a molecular structure is high and the polyimide fiber contains a phthalimide structure, and is excellent in chemical corrosion resistance, high temperature resistance, flame retardance, radiation resistance, heat insulation and other performances. The cotton fiber is a natural plant fiber and has good heat preservation performance.

The micro-nano fiber adopts CQ-M81-PP nano polypropylene slices. The melt temperature was 260 deg.C, the hot air temperature was 220 deg.C, the air pressure was 3atm, and the melt flow was 3.2 ml/min.

The air-jet spinning device for the micro-nano fibers comprises a device body 1, a V-shaped containing cavity 2 is arranged in the device body 1, a mandrel 3 for containing core yarns 4 to enter is arranged on the upper portion of the V-shaped containing cavity 2, a melt-blowing nozzle 5 for containing the micro-nano fibers to enter is arranged on the lateral portion of the device body 1, hot air inlets are formed in two sides of the melt-blowing nozzle 5 of the device body 1 and communicated with the V-shaped containing cavity 2, a plurality of compressed air inlets 6 are further arranged in the middle of the device body 1 and communicated with the V-shaped containing cavity 2, a plurality of pressure reduction exhaust holes 12 are further formed in the lower portion of the device body 1, and a yarn guide roller 8, a yarn guide roller 9, a bobbin yarn 10 and a winding roller 11 are sequentially arranged below a discharge port at the bottom of the V-shaped containing cavity 2.

As a further optimization of the above embodiment:

preferably, the radius of the V-shaped chamber 2 is gradually reduced from top to bottom.

Preferably, the mandrel 3 and the discharge port at the bottom of the V-shaped cavity 2 are coaxial.

Preferably, the upper part of the melting nozzle 5 is provided with a hot air inlet, and the lower part of the melting nozzle 5 is provided with four compressed air inlets 6 (as shown in fig. 4) which are symmetrical with each other.

Preferably, a deflector 7 is arranged below the melting nozzle 5.

Preferably, the angle a of the V-shaped chamber 2 ranges from 5 to 60. Length of V-shaped cavity: 100mm, the upper part inner diameter is 60mm, and the outlet inner diameter is 3 mm.

The working principle of the invention is as follows: high-speed hot air is sprayed into the spinning tube along the tangential direction at the upper end of the V-shaped air-jet spinning tube, rotates in the V-shaped cavity under the constraint of the spiral guide plate, and the micro-nano fibers are sprayed out by the hot melting nozzle and are continuously pulled, rotated and stretched under the guidance of hot air flow rotating at high speed. The four compressed air jet holes are distributed along the tangential direction, and the injected compressed air rotates, accelerates and cools the rotating hot air flow from the upper part of the V-shaped cavity, so that the micro-nano fibers are crystallized and formed during cooling. The diameter of the V-shaped spinning tube is smaller and smaller along with the downward movement of the airflow, the rotating speed is increased continuously, the micro-nano fiber further completes stretching and twisting under the guidance of the high-speed rotating airflow, a pressure reducing exhaust hole is formed in the lower portion of the V-shaped cavity, the high-speed rotating airflow is exhausted through the exhaust hole, the rotating micro-nano fiber is wound on the core yarn to form a coating yarn, the coating yarn is led out by a yarn leading roller and is wound into a cone yarn through a yarn guiding roller and a winding roller. The micro-nano fibers can be better coated on the surface of the core yarn by improving the rotating speed.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A micro-nanofiber covered yarn spinning process is characterized in that: the method comprises the following steps:

(1) preparing a core yarn;

(2) passing the core yarn through an air jet spinning device, and simultaneously coating the micro-nano fibers sprayed out by a hot melting nozzle on the surface of the core yarn to form a coated yarn by using an air jet principle; the air-jet spinning device comprises a device body (1), a V-shaped accommodating cavity (2) is arranged in the device body (1), a mandrel (3) for accommodating core yarns (4) to enter is arranged on the upper portion of the V-shaped accommodating cavity (2), a melt-blowing nozzle (5) for accommodating micro-nanofibers to enter is arranged on the lateral portion of the device body (1), hot air inlets are arranged on two sides of the melt-blowing nozzle (5) of the lateral portion of the device body (1), the hot air inlets are communicated with the V-shaped accommodating cavity (2), a plurality of compressed air inlets (6) are further arranged in the middle of the device body (1), the compressed air inlets (6) are communicated with the V-shaped accommodating cavity (2), a plurality of pressure reducing exhaust holes (12) are further arranged on the lower portion of the device body (1), and a yarn guiding roller (8) and a yarn guiding roller (9) are sequentially arranged below a discharge hole in the, A bobbin yarn (10) and a winding roller (11); the radius of the V-shaped cavity (2) is gradually reduced from top to bottom; the mandrel (3) and a discharge hole at the bottom of the V-shaped cavity (2) are coaxial; the upper part of the melting nozzle (5) is provided with a hot air inlet, and the lower part of the melting nozzle (5) is provided with four symmetrical compressed air inlets (6); a spiral guide plate (7) is arranged below the melting nozzle (5); the angle a of the V-shaped cavity (2) ranges from 5 degrees to 60 degrees;

the principle and the process of the air injection are as follows: at the upper end of the V-shaped air-jet spinning tube, high-speed hot air is sprayed into the spinning tube along the tangential direction, and rotates in the V-shaped cavity under the constraint of the spiral guide plate, and the micro-nano fibers are sprayed out by the hot melting nozzle and are continuously pulled, rotated and stretched under the guidance of hot air flow rotating at high speed; the four compressed air jet holes are distributed along the tangential direction, and the injected compressed air rotationally accelerates and cools the rotating hot air flow from the upper part of the V-shaped cavity, so that the micro-nano fibers are crystallized and formed during cooling; the diameter of the V-shaped spinning tube is smaller and smaller along with the downward movement of the airflow, the rotating speed is increased continuously, the micro-nano fibers are further stretched and twisted under the guidance of the high-speed rotating airflow, a pressure reducing exhaust hole is formed in the lower portion of the V-shaped cavity, and the high-speed rotating airflow is exhausted through the exhaust hole;

2. The micro-nanofiber covered yarn spinning process according to claim 1, characterized in that: the core yarn in the step (1) adopts siro compact spinning polyimide and long staple cotton combed blended yarn, and the mixing ratio of the combed long staple cotton to the polyimide is as follows: 20-80%: 80-20%, and the specific process comprises the following steps:

(2) drawing: carrying out secondary doubling on cotton slivers for carding, wherein the ration of the cotton slivers subjected to secondary doubling is controlled to be 17.5-23 g/5 m;

3. The micro-nanofiber covered yarn spinning process according to claim 1, characterized in that: and (3) adopting CQ-M81-PP nano polypropylene slices as the micro-nano fibers in the step (2).