CN-122013364-A - Cationic dyeable high-elastic hollow fiber and preparation method thereof

CN122013364ACN 122013364 ACN122013364 ACN 122013364ACN-122013364-A

Abstract

The embodiment of the invention provides a cationic dyeable high-elastic hollow fiber and a preparation method thereof. The modified melt and the common polyester melt are extruded out simultaneously through eccentric parallel round holes and C-shaped holes, and are cooled by side blowing and post-treated to directly form filaments. The method utilizes inherent crystallization and shrinkage differences of the two components to spontaneously generate permanent three-dimensional curling in the spinning forming process, so that high elasticity is obtained in one step, the damage to a hollow structure in the post-texturing process is thoroughly avoided, and the light thermal insulation property of the fiber is completely maintained. Meanwhile, the sulfonate group in the modified component enables the fiber to have cationic dye dyeability, and is combined with the disperse dye dyeability of the common component, so that a uniform bicolour effect can be realized on a single fiber, the processing applicability is strong, and the diversified requirements of high-end textiles are met.

Inventors

WANG ZHIPENG
Bao Ningning
ZHOU WENLONG
CHEN ZONGHAO
LU JIAYING
YANG TINGTING

Assignees

江苏恒科新材料有限公司

Dates

Publication Date: 20260512
Application Date: 20260129

Claims (10)

1. A method for preparing a cationic dyeable high-elastic hollow fiber, which is characterized by comprising the following steps: s1, taking refined terephthalic acid and ethylene glycol as raw materials, introducing isophthalic acid-5-sodium sulfonate accounting for 1 to 3 percent of the molar weight of the refined terephthalic acid and 1, 4-cyclohexanediol accounting for 5 to 10 percent of the molar weight of the refined terephthalic acid as comonomers in the polymerization process, and preparing modified polyethylene terephthalate melt through esterification reaction and polycondensation reaction; S2, conveying the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt to a metering pump through a melt distributing pipe after passing through a melt pump, a booster pump and a melt cooler; S3, after being metered by the metering pump, conveying the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt to a spinning component, extruding the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt by a spinneret plate formed by eccentrically and parallelly arranging round holes and C-shaped holes, and bonding the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt at an outlet of the spinneret plate to form a composite melt trickle; The modified polyethylene terephthalate melt is extruded from the round hole, and the unmodified polyethylene terephthalate melt is extruded from the C-shaped hole, wherein the mass ratio of the extrusion amount of the modified polyethylene terephthalate melt to the extrusion amount of the unmodified polyethylene terephthalate melt is 40:60 or 50:50; s4, carrying out side-air cooling on the composite melt trickle from one side of the round hole, and oiling, stretching, networking and winding the cooled composite melt trickle to obtain the cationic dyeable high-elastic hollow fiber.
2. The method according to claim 1, wherein step S1 specifically comprises: Mixing the refined terephthalic acid, the ethylene glycol and the 1, 4-cyclohexanediol to form a slurry, adding a catalyst and a stabilizer into the slurry, and carrying out esterification reaction at 250-260 ℃ under the pressurizing condition, wherein the mol ratio of the refined terephthalic acid to the ethylene glycol is 1:1.2-1:2.0, and the pressurizing condition is normal pressure to 0.3Mpa; When the distilled water amount reaches more than 90% of the theoretical value, adding the isophthalic acid-5-sodium sulfonate into a reaction system, and maintaining stirring for 25 to 30 minutes; the pressure is then reduced below an absolute pressure of 500 Pa, and the polycondensation reaction of the first stage is carried out at 260 to 270 ℃ for 30 to 50 minutes; The pressure is further reduced to below 100 Pa absolute, and the temperature is raised to 275-285 ℃ at the same time, and the second stage polycondensation reaction is carried out for 50-90 minutes, so as to obtain the modified polyethylene terephthalate melt.
3. The method according to claim 2, wherein the catalyst is any one of antimony trioxide, antimony glycol or antimony acetate, and the catalyst is added in an amount of 0.01% -0.05% by mass of the refined terephthalic acid.
4. A process according to claim 3, wherein the stabilizer is any one of triphenyl phosphate, trimethyl phosphate or trimethyl phosphite, and the stabilizer is added in an amount of 0.01% to 0.05% by mass of the purified terephthalic acid.
5. The method according to claim 4, wherein the opening width of the C-shaped hole is 0.15-0.25mm, the outer diameter is 0.45-0.5mm, the inner diameter is 0.3-0.35mm, the diameter of the round hole is 0.25-0.3mm, and the shortest distance between the round hole and the C-shaped hole is 0.07-0.08mm.
6. The method of claim 5 wherein the windless zone of the spinneret has a height of 50-70mm.
7. The method according to claim 6, wherein in step S4, the pressure of the side air is 50 to 60Pa and the temperature is 25 to 30 ℃.
8. The method according to claim 7, wherein, in step S4, The height of the oil frame in the oiling process is 900-1200mm; The stretching process adopts two-stage hot rolls to carry out hot stretching, wherein the temperature of the first hot roll is 60-80 ℃, the shaping temperature of the second hot roll is 120-140 ℃, and the stretching multiple is 2-3 times; the spinning speed of the winding process is 2500-2800 m/min.
9. The method of claim 8 wherein the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt are spun at a temperature of from 260 ℃ to 280 ℃ prior to extrusion and a spinneret initial pressure of from 8 to 12 MPa.
10. A cationically dyeable high elastic hollow fiber, characterized in that said fiber is prepared by the process according to any one of claims 1 to 9.

Description

Cationic dyeable high-elastic hollow fiber and preparation method thereof Technical Field The invention relates to the technical field of chemical fiber manufacturing, in particular to a cationic dyeable high-elastic hollow fiber and a preparation method thereof. Background The hollow fiber, especially the hollow polyester fiber, has excellent heat insulation and light weight because the static air layer sealed inside can effectively separate heat conduction, and has become an indispensable important raw material in high-end heat insulation quilt cores, down jackets, jacket liners and various light-weight heat insulation clothes. With the increasing demands of the consumer market on the multifunction, comfort and aesthetic degree of textiles, the development of hollow fibers with excellent warmth retention, good elasticity and rich dyeing effects becomes an important research direction in the field of textile materials. At present, the industrially conventional hollow fiber is mainly extruded from Polyester (PET) melt through a spinneret orifice with a special shape, expanded and bonded by the 'Basex effect' of the melt to form a hollow structure, and then subjected to hot drawing to prepare Fully Drawn Yarn (FDY). However, conventional hollow FDY fibers obtained by this method are not inherently elastic. In order to impart elasticity, it is necessary to carry out complicated post-processing by an additional texturing machine, and the yarn is deformed by heating in a high-temperature hot box and high-speed mechanical friction in a false twister. This post-processing is a common technical path in the art to obtain elastic hollow filaments. The above method of imparting elasticity to hollow FDY by elasticizer has significant drawbacks. Firstly, under the high-speed rotating friction of the false twister disc and the high-temperature action of a hot box, the fiber, especially the fragile hollow pipe wall, is subjected to huge shearing force and thermal stress, and the pipe wall is extremely easy to crack, squeeze and deform or collapse of the hollow structure, so that the core advantage of the fiber, namely the warmth retention property, is greatly reduced. Secondly, this intense post-processing process tends to cause uneven damage to the fibrous structure, which in turn leads to poor uniformity of subsequent dyeing. In addition, in the dyeing style, the conventional polyester fiber can be dyed with only a disperse dye, and has a single color. To obtain the bicolor effect, the industry generally needs to ply and blend hollow fibers and cationic dyeable fibers on a texturing machine, which is complex in process, high in cost, more limited in processing of ply texturing (for example, often limited to thicker specifications), and further aggravates the damage to the hollow structure. Therefore, how to directly prepare the hollow fiber with high elasticity and cationic dyeability by a one-step method on the premise of not damaging the hollow structure becomes a difficult problem to be solved in the prior art. Disclosure of Invention In view of the above problems, it has been proposed to provide a cationic dyeable high-elastic hollow fiber and a method for preparing the same, which overcome or at least partially solve the above problems, in particular: A preparation method of a cationic dyeable high-elastic hollow fiber comprises the following steps: S1, taking refined terephthalic acid and ethylene glycol as raw materials, introducing isophthalic acid-5-sodium sulfonate accounting for 1 to 3 percent of the molar weight of the refined terephthalic acid and 1, 4-cyclohexanediol accounting for 5 to 10 percent of the molar weight of the refined terephthalic acid as comonomers in the polymerization process, and preparing a modified polyethylene terephthalate melt through esterification reaction and polycondensation reaction; S2, conveying the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt to a metering pump through a melt distributing pipe after passing through a melt pump, a booster pump and a melt cooler; S3, after metering by a metering pump, conveying the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt to a spinning component, extruding the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt by a spinneret plate formed by eccentrically and parallelly arranging round holes and C-shaped holes, and bonding the modified polyethylene terephthalate melt and the unmodified polyethylene terephthalate melt at an outlet of the spinneret plate to form a composite melt trickle; the mass ratio of the extrusion amount of the modified polyethylene terephthalate melt to the extrusion amount of the unmodified polyethylene terephthalate melt is 40:60 or 50:50; s4, carrying out cross-air cooling on the composite melt trickle from one side of the round hole, and oiling, stretching, networking and winding the