Preparation method of acid-opening polyester-polyamide composite fabric

Abstract

The application relates to the technical field of textiles and discloses a preparation method of an acid open-fiber polyester-polyamide composite fabric, which comprises the following steps: (1) preparing polyester-polyamide composite superfine fibers: preparing polyester-polyamide composite superfine fibers by using copolyether ester and polyamide; the copolyether ester is a block copolymer composed of a soft segment and a hard segment, and the soft segment is polytetrahydrofuran; (2) weaving and open-fiber treatment of the composite fabric: weaving the polyester-polyamide composite superfine fibers into a fabric, and then performing open-fiber treatment by using an organic acid solution to obtain the acid open-fiber polyester-polyamide composite fabric. In the preparation process of the polyester-polyamide composite fabric, the copolyether ester containing the polytetrahydrofuran soft segment is used as the polyester component in the polyester-polyamide composite superfine fibers, and the organic acid solution treatment is performed, so that the open-fiber treatment is realized under the acid condition; the preparation process has little pollution to the environment; and the obtained polyester-polyamide composite fabric has good dyeing performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of textiles, and particularly relates to a preparation method of acid open-fiber polyester-polyamide composite fabric. BACKGROUND

[0002] In recent years, with the development of petrochemical integration technology, synthetic fibers have gradually increased in the textile industry due to their wide raw material sources and excellent performance, and polyester and polyamide have become two fibers with the largest output and consumption in synthetic fibers. Polyester-polyamide composite ultra-fine fiber is a new type of differential fiber. The composite fiber before opening is not much different from ordinary fiber. After opening treatment, it can be divided into multiple fibers, reducing the diameter and fineness of the fiber to 1 / 8-1 / 40 of the original, and the specific surface area is also several times higher. Therefore, the fabric woven by the composite fiber has soft hand feeling and unique style.

[0003] Polyester-polyamide composite ultra-fine fiber is made by melt spinning of polyester and polyamide through a composite spinning assembly. Because the interfacial bonding force of polyester and polyamide is weak, chemical opening, physical opening or a combination of both are usually used to separate them. During the separation process, due to the different shrinkage rates of the two components, the fiber with a larger shrinkage rate shortens in the radial length, causing the other component fiber to protrude and form dense small loops, achieving the effect of raising. Therefore, the polyester-polyamide composite ultra-fine fiber fabric has good capillary wicking performance, excellent hydrophobic and moisture-wicking performance and good wearing comfort.

[0004] From the current processing technology, polyester-polyamide composite fibers generally use alkali treatment opening process (such as patent CN105506879A uses a two-step opening method, first alkali weight reduction opening, and then mechanical opening). This method faces two problems: first, the structure of polyester fiber is damaged. When different types of polyester raw materials are selected, the alkali concentration, treatment time and temperature need to be adjusted to the appropriate range. The weight loss rate of the opened composite fiber reaches 10%-20%, and the reduction of the polyester component reduces the dyeing rate of disperse dyes. Second, in order to reduce the damage of alkali to polyester fiber, low concentration alkali is generally used while the treatment time is prolonged. This not only produces a large amount of organic wastewater, but also causes environmental pollution and increases production cost. SUMMARY

[0005] In order to solve the technical problems of poor dyeing performance and environmental pollution of the existing polyester-polyamide composite ultra-fine fiber opening process, the present application provides a preparation method of acid open-fiber polyester-polyamide composite fabric. The preparation method has less damage to the polyester component in the composite fiber, can make the prepared polyester-polyamide composite fabric have good dyeing performance, and has little environmental pollution in the preparation process.

[0006] The specific technical scheme of the present application is as follows:

[0007] In a first aspect, the present application provides a preparation method of acid-opened polyester-polyamide composite fabric, comprising the following steps:

[0008] (1) Preparation of polyester-polyamide composite ultrafine fiber: prepare polyester-polyamide composite ultrafine fiber from copolyether ester and polyamide; the copolyether ester is a block copolymer composed of soft segment and hard segment, and the soft segment is polytetrahydrofuran;

[0009] (2) Weaving and opening treatment of composite fabric: weave the polyester-polyamide composite ultrafine fiber into fabric, and then perform organic acid solution treatment to open the fabric, thereby obtaining acid-opened polyester-polyamide composite fabric.

[0010] In the present application, the copolyether ester containing polytetrahydrofuran soft segment is used as the polyester component in the polyester-polyamide composite ultrafine fiber, and the organic acid solution treatment is performed, so that the opening under acid conditions can be realized. Specifically, in the organic acid treatment process, the ether bond oxygen atoms in the polytetrahydrofuran soft segment are prone to form hydrogen bonds with the acidic groups in the organic acid due to the electron-withdrawing effect, so that the polyester-polyamide components in the polyester-polyamide composite ultrafine fiber are separated from each other, the polyester (copolyether ester) fiber shrinks in the radial length, and the polyamide (polyamide) fiber with a smaller shrinkage rate protrudes to become small loops on the surface of the fabric, thereby achieving the raising effect. The copolyether ester component has good dyeing performance, and the dyeing performance of the polyamide component is relatively poor. In the present application, the opening is performed in the above manner, so that the damage to the polyester fiber structure is small, the loss of the polyester component in the opened composite fiber is small, and thus the composite fabric obtained has good dyeing performance. Moreover, the opening method of the present application is simple, and a large amount of organic wastewater is not generated, so that the environmental pollution is small.

[0011] Preferably, in step (1), the total chain length of all soft segments in the copolyether ester accounts for 40-50% of the total chain length of the copolyether ester.

[0012] In the copolyether ester, the polytetrahydrofuran soft segment can enable the polyester-polyamide composite ultrafine fiber to be opened under acid conditions. With the increase of the content of the polytetrahydrofuran soft segment, the acid-opening effect of the polyester-polyamide composite ultrafine fiber is improved. However, when the content of the polytetrahydrofuran soft segment in the copolyether ester is too high, the strength of the polyester-polyamide composite ultrafine fiber will decrease. In the present application, the content of the polytetrahydrofuran soft segment is controlled to be 40-50%, so that the polyester-polyamide composite ultrafine fiber has both high strength and good acid-opening effect.

[0013] Preferably, in step (1), the weight average molecular weight of the soft segment in the copolyether ester is 1000-3000 g / mol.

[0014] Preferably, in step (1), the hard segment in the copolyether ester is polyethylene terephthalate.

[0015] As preferred, in step (2), the pH of the acid solution is controlled to be 4-5, the temperature is controlled to be 110-125℃, and the time is controlled to be 40-50min during the process of treating the opened fabric with the organic acid solution.

[0016] The shrinkage and the degree of raising of the fabric can be adjusted by adjusting the opening temperature, so the thickness, the softness and the hardness of the fabric can be changed flexibly according to the characteristics of the product application.

[0017] As preferred, in step (2), the process of treating the opened fabric with the organic acid solution is combined with dyeing, and the specific process comprises the following steps: immersing the fabric in a dyeing solution containing the organic acid, and performing heat treatment.

[0018] The opening step is combined in the dyeing and finishing process, which reduces the washing times of the fabric, greatly reduces the consumption of water and energy, improves the production efficiency, saves energy and reduces the pollution to the environment.

[0019] As preferred, in step (2), the organic acid is glacial acetic acid.

[0020] As preferred, in step (1), the mass ratio of the copolyether ester and the polyamide is 70:30-60:40.

[0021] As preferred, in step (1), the intrinsic viscosity of the copolyether ester is 0.50-1.20dl / g, and the relative viscosity of the polyamide is 2.40-3.30dl / g.

[0022] As preferred, the specific process of step (1) comprises the following steps: melting the dry copolyether ester chips and the polyamide chips respectively, performing composite spinning, and performing drawing, heat setting and winding to obtain the PET / PA composite ultrafine fiber.

[0023] Further, in the process of composite spinning, the cross section of the spinneret is orange segment type or rice character type.

[0024] Further, in the process of composite spinning, the spinning temperature of the copolyether ester is 260-295℃, and the spinning temperature of the polyamide is 255-275℃.

[0025] Further, in the process of composite spinning, the cooling forming is performed by using side blowing, the temperature of the side blowing is 20-30℃, the speed of the side blowing is 0.30-0.60m / s, and the humidity of the side blowing is 75±5%.

[0026] Further, the drawing and heat setting are performed by using the first heat roller and the second heat roller, the temperature of the first heat roller is 70-90℃, the temperature of the second heat roller is 130-160℃, and the draw ratio is 2.5-4.0.

[0027] The first heat roller heats the fiber to the vicinity of the glass transition temperature, and the temperature is generally controlled between 70-90 DEG C, and the breaking strength and elongation of the fiber are increased with the increase of the temperature of the first heat roller. The second heat roller crystallizes and sets the fiber at high temperature, and the setting temperature of the heat setting has a direct influence on the tensile stress and the boiling water shrinkage of the fiber.

[0028] Further, the winding speed is 2800-4500 m / min.

[0029] Preferably, in step (2), the specific process of weaving the fabric comprises the following steps: after the polyester-polyamide composite ultra-fine fiber warp yarn and the polyester-polyamide composite ultra-fine fiber weft yarn are sized with starch-based size, weaving is performed, and then desizing and cleaning are performed to obtain a gray fabric.

[0030] In a second aspect, the application provides an acid-opened polyester-polyamide composite fabric prepared by the preparation method.

[0031] Compared with the prior art, the application has the following advantages:

[0032] (1) In the preparation process of the polyester-polyamide composite fabric, the copolyether ester containing polytetrahydrofuran soft segments is used as the polyester component in the polyester-polyamide composite ultra-fine fiber, and the organic acid solution treatment is performed, so that the fiber opening is realized under the acid condition, the preparation process has little pollution to the environment, and the obtained polyester-polyamide composite fabric has good dyeing performance.

[0033] (2) The polyester-polyamide composite fabric prepared by the application has soft and silky hand feeling, delicate and lasting fluff feeling, soft surface luster, moisture absorption and sweat release, and good elasticity, and has very high comfort while having the characteristics of polyester and polyamide. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a cross-sectional view of the composite ultra-fine fiber after opening in the application;

[0035] Figure 2 is a cross-sectional view of the composite ultra-fine fiber before opening in the application;

[0036] Figure 3 is a schematic view of the fabric structure of the three-over-one twill;

[0037] Figure 4 is a process flow chart of the preparation process of the acid-opened polyester-polyamide composite fabric in the application. DETAILED DESCRIPTION

[0038] The application will be further described below in combination with examples.

[0039] It should be understood that the following examples are merely illustrative and explanatory in nature and are not to be construed as limiting the scope of the present application. Any technique based on the above description of the present application is encompassed within the scope of the present application.

[0040] The methods used in the following examples are conventional methods in the art unless otherwise specified; the reagents, materials, equipment, etc. used in the following examples are commercially available unless otherwise specified.

[0041] General Examples

[0042] A method for preparing an acid-opened polyester-polyamide composite fabric, comprising the following steps:

[0043] (1) Preparation of polyester-polyamide composite ultrafine fibers: polyester-polyamide composite ultrafine fibers are prepared from copolyether ester and polyamide; the copolyether ester is a block copolymer composed of soft segments and hard segments, and the soft segments are polytetrahydrofuran;

[0044] (2) Weaving and opening treatment of the composite fabric: the polyester-polyamide composite ultrafine fibers are woven into a fabric, and then treated with an organic acid solution to open the fibers, thereby obtaining an acid-opened polyester-polyamide composite fabric.

[0045] As a specific embodiment, in step (1), the total chain length of all soft segments in the copolyether ester accounts for 40-50% of the total chain length of the copolyether ester, and the weight average molecular weight of the soft segments is 1000-3000 g / mol.

[0046] As a specific embodiment, in step (1), the hard segments in the copolyether ester are polyethylene terephthalate.

[0047] As a specific embodiment, in step (1), the mass ratio of the copolyether ester to the polyamide is 70:30-60:40, the intrinsic viscosity of the copolyether ester is 0.50-1.20 dl / g, and the relative viscosity of the polyamide is 2.40-3.30 dl / g.

[0048] As a specific embodiment, the specific process of step (1) comprises the following steps: melt the dry copolyether ester chips and polyamide chips respectively, then perform composite spinning, adopt orange peel type or rice character type spinneret section, the spinning temperature of copolyether ester is 260-295℃, the spinning temperature of polyamide is 255-275℃, adopt side blowing way to cool and form, the side blowing temperature is 20-30℃, the side blowing speed is 0.30-0.60m / s, the side blowing humidity is 75±5%; then adopt the first hot roller and the second hot roller to perform drafting heat setting, the first hot roller temperature is 70-90℃, the second hot roller temperature is 130-160℃, the draw ratio is 2.5-4.0, then perform winding at the speed of 2800-4500m / min, and the polyester-polyamide composite superfine fiber is obtained.

[0049] As a specific embodiment, in step (2), the specific process of fabric weaving comprises the following steps: adopt starch type sizing agent to size the polyester-polyamide composite superfine fiber warp yarn and polyester-polyamide composite superfine fiber weft yarn, then perform weaving, and then perform desizing and cleaning and oil removal, and the grey fabric is obtained.

[0050] As a specific embodiment, in step (2), in the process of treating the fibrillation with the organic acid solution, the pH of the acid solution is controlled to be 4-5, the temperature is controlled to be 110-125℃, and the time is controlled to be 40-50min.

[0051] As a specific embodiment, in step (2), the fibrillation treatment with the organic acid solution is performed together with dyeing, and the specific process comprises the following steps: immerse the grey fabric in the dyeing solution containing the organic acid, and perform heat treatment.

[0052] As a specific embodiment, in step (2), the organic acid is glacial acetic acid.

[0053] Example 1

[0054] The acid fibrillation polyester-polyamide composite fabric is prepared by the following steps (the flow chart is shown in Figure 4 ) :

[0055] (1) Preparation of copolyether ester chips:

[0056] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then slurried in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, the pressure is further increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, so that the total chain length of the polytetrahydrofuran soft segment accounts for 45% of the chain length of the copolyether ester finally prepared, the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized to obtain copolyether ester chips.

[0057] (2) Preparation of PET / PA composite ultrafine fibers:

[0058] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.64 dl / g, and the relative viscosity of the polyamide chips is 3.00 dl / g.

[0059] (2.2) The two kinds of chips are drum-dried and then fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 280°C / 290°C / 300°C / 295°C, and the screw temperature of the polyamide chips is 260°C / 270°C / 280°C / 280°C.

[0060] (2.3) The obtained two kinds of melts are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component is 70:30 during spinning, the spinning box temperature of the copolyether ester is 290°C, the spinning box temperature of the polyamide is 275°C, and a cross-shaped spinneret plate is used in the composite spinning assembly. The two kinds of melts form streams at the spinneret plate, are extruded from the spinneret holes, and are then cooled and formed into a composite yarn through side blowing, the side blowing temperature is 20°C, the side blowing speed is 0.50 m / s, and the side blowing humidity is 73%, and the composite yarn is obtained.

[0061] (2.4) The composite yarn is fed into a spinning duct for oiling, and then is drawn and heat-set through a first hot roller and a second hot roller, the first hot roller temperature is 70°C, the second hot roller temperature is 140°C, the draw ratio is 3.0, and finally winding is carried out at a winding speed of 3500 m / min, and PET / PA composite ultrafine fibers are obtained.

[0062] The PET / PA composite ultrafine fibers prepared in this example have the following properties: the breaking strength is 3.92 cN / dtex, the breaking elongation is 35.80%, and the boiling water shrinkage is 12%.

[0063] (3) Weaving and fibrillation treatment of the composite fabric:

[0064] (3.1) S / P composite ultrafine fiber warp and S / P composite ultrafine fiber weft are sized (starch) and then woven. The fabric structure is three over one twill (as shown in Figure 3 ), the warp density is 330 ends / 10 cm, and the weft density is 270 ends / 10 cm.

[0065] (3.2) Desizing: hot water washing (75°C, 10 min), immersion in working solution (working solution: containing amylase, 80°C, 30 min), hot water washing, and cold water washing.

[0066] (3.3) Fabric washing: unwinding, water washing (containing oil removing agent CL911 g / L), clean water washing, and obtaining the fabric, the fiber cross section of which is shown in Figure 2 .

[0067] (3.4) Dyeing and fiber opening: high temperature and high pressure overflow cylinder is used, and the dyeing solution formula is as follows: disperse dye S-3BG blue (the amount is 0.5% of the weight of the fabric), disperse uniform agent leveling agent XPO-5 (the content in the dyeing solution is 1 g / L), the solvent is water, and the bath ratio is 1:10. The dyeing solution is heated to 30°C, and the pH is adjusted to 4 with glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is injected into the feeding barrel, slowly injected, and then heated to 125°C at a rate of 1°C / min, kept for 40 min, and then cooled to 70°C at a rate of 0.5°C / min. The composite fabric after dyeing is taken out, and the fiber cross section is shown in Figure 1 , the comparison Figure 1 and Figure 2 indicate that the composite fabric has successfully realized fiber opening. It is measured that the weight loss rate after fiber opening is 3.7%, the fiber opening rate is 96%, and the dyeing rate is 98%.

[0068] (3.5) Setting, temperature is 170°C, and the speed is 50 m / min.

[0069] (3.6) Finished product inspection.

[0070] Example 2

[0071] An acid fiber opening S / P composite fabric is prepared by the following steps (the flow chart is shown in Figure 4 ):

[0072] (1) Preparation of copolyether ester chip:

[0073] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then milled in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, the pressure is further increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, so that the total chain length of the polytetrahydrofuran soft segment accounts for 50% of the chain length of the copolyether ester finally prepared, the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized to obtain copolyether ester chips.

[0074] (2) Preparation of PET / PA composite ultrafine fibers:

[0075] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.70 dl / g, and the relative viscosity of the polyamide chips is 2.80 dl / g.

[0076] (2.2) The two kinds of chips are drum-dried and then respectively fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 285°C / 295°C / 310°C / 300°C, and the screw temperature of the polyamide chips is 260°C / 265°C / 280°C / 270°C.

[0077] (2.3) The obtained two kinds of melts are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component is 65:35 during spinning, the spinning box temperature of the copolyether ester is 295°C, the spinning box temperature of the polyamide is 270°C, and an orange segment type spinneret is used in the composite spinning assembly. The two kinds of melts form streams at the spinneret and are extruded from the spinneret holes, and then are cooled and formed into a composite yarn through side blowing.

[0078] (2.4) The composite yarn is fed into a spinning duct for oiling, and then is drawn and heat-set through a first hot roller and a second hot roller, the first hot roller temperature is 80°C, the second hot roller temperature is 150°C, the draw ratio is 2.8, and finally winding is carried out at a winding speed of 4000 m / min to obtain PET / PA composite ultrafine fibers.

[0079] The PET / PA composite ultrafine fibers prepared in this example have the following properties: the breaking strength is 4.07 cN / dtex, the breaking elongation is 33.54%, and the boiling water shrinkage is 10%.

[0080] (3) Weaving and fibrillation treatment of the composite fabric:

[0081] (3.1) S / P composite ultrafine fiber warp yarn and S / P composite ultrafine fiber weft yarn are sized (starch) and then woven. The fabric structure is three over one twill (as shown in Figure 3 ), the warp density is 330 ends / 10 cm, and the weft density is 270 ends / 10 cm.

[0082] (3.2) Desizing: hot water washing (75 °C, 10 min), immersion in working solution (working solution: containing amylase, 80 °C, 30 min), hot water washing, and cold water washing.

[0083] (3.3) Fabric washing: unwinding, water washing (containing oil removing agent CL911 g / L), and clean water washing to obtain the fabric.

[0084] (3.4) Dyeing and fiber opening: high temperature and high pressure overflow cylinder is used, and the dyeing solution formula is as follows: disperse dye S-3BG blue (the amount is 0.5% of the weight of the fabric), disperse uniform agent leveling agent XPO-5 (the content in the dyeing solution is 1 g / L), solvent is water, and bath ratio is 1:10. The dyeing solution is heated to 30 °C, and the pH is adjusted to 4 by glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is slowly injected into the feeding barrel, and then the temperature is increased to 110 °C at a rate of 1 °C / min, and kept for 40 min, and then decreased to 70 °C at a rate of 0.5 °C / min. It is measured that the weight loss rate after fiber opening is 3.0%, the opening rate is 95%, and the dyeing rate is 96%.

[0085] (3.5) Fixing, temperature is 170 °C, and the speed is 50 m / min.

[0086] (3.6) Product inspection.

[0087] Example 3

[0088] An acid fiber opening S / P composite fabric is prepared by the following steps (the flow chart is shown in Figure 4 ):

[0089] (1) Preparation of copolyether ester chip:

[0090] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then slurried in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, the pressure is further increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, the total chain length of the polytetrahydrofuran soft segment accounts for 44% of the chain length of the copolyether ester finally prepared, the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized to obtain copolyether ester chips.

[0091] (2) Preparation of polyester-polyamide composite ultrafine fibers:

[0092] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.60 dl / g, and the relative viscosity of the polyamide chips is 3.20 dl / g.

[0093] (2.2) The two kinds of chips are drum-dried and then fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 285°C / 295°C / 300°C / 300°C, and the screw temperature of the polyamide chips is 260°C / 265°C / 280°C / 280°C.

[0094] (2.3) The two kinds of melts obtained are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component during spinning is 65:35, the spinning box temperature of the copolyether ester is 295°C, the spinning box temperature of the polyamide is 275°C, and an orange segment type spinneret is used in the composite spinning assembly. The two kinds of melts form streams at the spinneret and are extruded from the spinneret holes, and then are cooled and formed into a composite yarn through side blowing, the side blowing temperature is 23°C, the side blowing speed is 0.50 m / s, and the side blowing humidity is 75%, and the composite yarn is obtained.

[0095] (2.4) The composite yarn is fed into a spinning duct for oiling, and then is drawn and heat set through a first hot roller and a second hot roller, the first hot roller temperature is 75°C, the second hot roller temperature is 145°C, the draw ratio is 3.2, and finally the yarn is wound at a winding speed of 4000 m / min, and polyester-polyamide composite ultrafine fibers are obtained.

[0096] The polyester-polyamide composite ultrafine fibers prepared in this example have the following properties: the breaking strength is 4.25 cN / dtex, the breaking elongation is 38.46%, and the boiling water shrinkage is 14%.

[0097] (3) Weaving and fibrillation treatment of the composite fabric:

[0098] (3.1) S / P composite ultrafine fiber warp yarn and S / P composite ultrafine fiber weft yarn are sized (starch) and then woven. The fabric structure is three over one twill (as shown in Figure 3 ), the warp density is 370 ends / 10 cm, and the weft density is 300 ends / 10 cm.

[0099] (3.2) Desizing: hot water washing (75 °C, 10 min), immersion in working solution (working solution containing amylase, 80 °C, 30 min), hot water washing, and cold water washing.

[0100] (3.3) Fabric washing: unwinding, water washing (containing oil removing agent CL911 g / L), and clean water washing to obtain the fabric.

[0101] (3.4) Dyeing and fiber opening: high temperature and high pressure overflow cylinder is used, and the dyeing solution is as follows: disperse dye S-3BG blue (0.5% of the weight of the fabric), disperse leveling agent XPO-5 (1 g / L in the dyeing solution), solvent is water, and bath ratio is 1:10. The dyeing solution is heated to 30 °C, and the pH is adjusted to 4 with glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is slowly injected into the feeding barrel, and then the temperature is raised to 125 °C at a rate of 1 °C / min, and kept for 40 min, and then the temperature is lowered to 70 °C at a rate of 0.5 °C / min. It is measured that the weight loss rate after fiber opening is 3.6%, the fiber opening rate is 93%, and the dyeing rate is 96%.

[0102] (3.5) Fixing, temperature is 170 °C, and the speed is 50 m / min.

[0103] (3.6) Finished product inspection.

[0104] Example 4

[0105] The acid fiber opening S / P composite fabric is prepared by the following steps (the flow chart is shown in Figure 4 ):

[0106] (1) Preparation of copolyether ester chip:

[0107] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then slurried in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, the pressure is further increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, so that the total chain length of the polytetrahydrofuran soft segment accounts for 40% of the chain length of the copolyether ester finally prepared, the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized, to obtain copolyether ester chips.

[0108] (2) Preparation of polyester-polyamide composite ultrafine fibers:

[0109] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.50 dl / g, and the relative viscosity of the polyamide chips is 3.20 dl / g.

[0110] (2.2) The two kinds of chips are drum-dried and then fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 275°C / 280°C / 285°C / 280°C, and the screw temperature of the polyamide chips is 260°C / 265°C / 280°C / 280°C.

[0111] (2.3) The two kinds of melts obtained are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component is 65:35 during spinning, the spinning box temperature of the copolyether ester is 285°C, the spinning box temperature of the polyamide is 275°C, and an orange segment type spinneret is used in the composite spinning assembly. The two kinds of melts form streams at the spinneret and are extruded from the spinneret holes, and then are cooled and formed into a composite yarn through side blowing.

[0112] (2.4) The composite yarn is fed into a spinning duct for oiling, and then is drawn and heat-set through a first hot roller and a second hot roller, the first hot roller temperature is 75°C, the second hot roller temperature is 145°C, the draw ratio is 3.3, and finally the yarn is wound at a winding speed of 4000 m / min, to obtain polyester-polyamide composite ultrafine fibers.

[0113] The polyester-polyamide composite ultrafine fibers prepared in this example have the following properties: the breaking strength is 4.15 cN / dtex, the elongation at break is 37.14%, and the boiling water shrinkage is 13%.

[0114] (3) Weaving and fibrillation treatment of the composite fabric:

[0115] (3.1) S / P composite ultrafine fiber warp yarn and S / P composite ultrafine fiber weft yarn are sized (starch) and then woven, and the fabric structure is three over one twill (as shown in Figure 3 ), with warp density of 370 ends / 10 cm and weft density of 300 ends / 10 cm.

[0116] (3.2) Desizing: hot water washing (75°C, 10 min), immersion in working solution (working solution containing amylase, 80°C, 30 min), hot water washing, and cold water washing.

[0117] (3.3) Fabric cleaning: unrolling and water washing (containing oil removing agent CL911 g / L), and clean water washing to obtain the fabric.

[0118] (3.4) Dyeing and fiber opening: high temperature and high pressure overflow cylinder is used, and the dyeing solution is as follows: disperse dye S-3BG blue (0.5% of the weight of the fabric), disperse leveling agent XPO-5 (1 g / L in the dyeing solution), solvent is water, and bath ratio is 1:10. The dyeing solution is heated to 30°C, and the pH is adjusted to 5 by glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is slowly injected into the feeding barrel, and then the temperature is increased to 125°C at a rate of 1°C / min, and kept for 40 min, and then decreased to 70°C at a rate of 0.5°C / min. It is measured that the weight loss rate after fiber opening is 3.3%, the opening rate is 95%, and the dyeing rate is 97%.

[0119] (3.5) Fixing, temperature is 170°C, and the speed is 50 m / min.

[0120] (3.6) Product inspection.

[0121] Data analysis: in examples 1-4, the opening rate is higher than 90%, the dyeing rate is higher than 95%, and the weight loss rate after fiber opening is less than 4%, which is significantly lower than the traditional alkali treatment opening of 10%-20%. It is shown that the S / P composite ultrafine fiber prepared by the method of the present application can realize acid opening, and the damage to the polyester component in the opening process is small, and the obtained composite fabric has good dyeing performance.

[0122] Example 5

[0123] The acid opening S / P composite fabric is prepared by the following steps (flow chart is shown in Figure 4 ):

[0124] (1) Preparation of copolyether ester chip:

[0125] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then milled in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, and then the pressure is increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, the total chain length of the polytetrahydrofuran soft segment accounts for 30% of the chain length of the final copolyether ester, and the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, and after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized to obtain copolyether ester chips.

[0126] (2) Preparation of polyester-polyamide composite ultrafine fibers:

[0127] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.43 dl / g, and the relative viscosity of the polyamide chips is 3.20 dl / g.

[0128] (2.2) The two kinds of chips are drum-dried and then fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 275°C / 280°C / 285°C / 280°C, and the screw temperature of the polyamide chips is 260°C / 265°C / 280°C / 280°C.

[0129] (2.3) The obtained two kinds of melts are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component during spinning is 65:35, the spinning box temperature of the copolyether ester is 285°C, the spinning box temperature of the polyamide is 275°C, and segmented orifice spinnerets are used in the composite spinning assembly. The two kinds of melts form streams at the spinnerets, are extruded from the spinneret holes, and are then cooled and formed into fibers by side blowing, the side blowing temperature is 23°C, the side blowing speed is 0.50 m / s, and the side blowing humidity is 75%, and a composite yarn is obtained.

[0130] (2.4) The composite yarn is fed into a spinning duct for oiling, and then drawn and heat-set by a first hot roller and a second hot roller, the first hot roller temperature is 75°C, the second hot roller temperature is 145°C, the draw ratio is 3.3, and finally wound, the winding speed is 4000 m / min, and a polyester-polyamide composite ultrafine fiber is obtained.

[0131] The polyester-polyamide composite ultrafine fiber prepared in this example has the following properties: the breaking strength is 4.93 cN / dtex, the elongation at break is 34.03%, and the boiling water shrinkage is 10%.

[0132] (3) Weaving and fibrillation treatment of the composite fabric:

[0133] (3.1) S / P composite ultrafine fiber warp yarn and S / P composite ultrafine fiber weft yarn are sized (starch) and then woven. The fabric structure is three over one twill (as shown in Figure 3 ), the warp density is 370 ends / 10 cm, and the weft density is 300 ends / 10 cm.

[0134] (3.2) Desizing: hot water washing (75°C, 10 min), immersion in working solution (working solution containing amylase, 80°C, 30 min), hot water washing, and cold water washing.

[0135] (3.3) Fabric washing: unwinding, water washing (containing oil removing agent CL911 g / L), clean water washing, and obtaining of the fabric.

[0136] (3.4) Dyeing and fiber opening: high temperature and high pressure overflow cylinder is used, and the dyeing solution formula is as follows: disperse dye S-3BG blue (0.5% of the weight of the fabric), disperse uniformizing agent leveling agent XPO-5 (1 g / L in the dyeing solution), solvent is water, and bath ratio is 1:10. The dyeing solution is heated to 30°C, and the pH is adjusted to 5 with glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is slowly injected into the feeding barrel, and then the temperature is increased to 125°C at a rate of 1°C / min, and kept for 40 min, and then decreased to 70°C at a rate of 0.5°C / min. It is measured that the weight loss rate after fiber opening is 2.8%, the fiber opening rate is 86%, and the dyeing rate is 91%.

[0137] (3.5) Fixing, temperature is 170°C, and the speed is 50 m / min.

[0138] (3.6) Finished product inspection.

[0139] Data analysis: compared with Example 4, the fiber opening rate of Example 5 is obviously lower. It is indicated that when the content of polytetrahydrofuran soft segment in the copolyether ester is reduced, the acid fiber opening effect of S / P composite ultrafine fiber will be reduced.

[0140] Example 6

[0141] The acid fiber opening S / P composite fabric is prepared by the following steps (the process is shown in Figure 4 ):

[0142] (1) Preparation of copolyether ester chips:

[0143] The terephthalic acid, ethylene glycol, and ethylene glycol antimony are mixed and then slurried in a reaction vessel, the alcohol acid ratio is 1:1.2, and the catalyst is added in an amount of 240 ppm; nitrogen is introduced into the reaction vessel, the initial pressure is increased to 0.10 MPa, the temperature is increased to 245°C, the pressure is further increased to 0.3 MPa, the esterification reaction is carried out for 2.5 h, and the byproduct water is continuously removed; after the esterification is completed, polytetrahydrofuran with a weight average molecular weight of 1500 g / mol is added, so that the total chain length of the polytetrahydrofuran soft segment accounts for 60% of the chain length of the copolyether ester finally prepared, the reaction is continued for 0.5 h, and then the pre-polycondensation reaction is carried out at a vacuum of -0.09 MPa and a temperature of 270°C for 1 h; then the polycondensation reaction is carried out at a high vacuum of 50 Pa and a temperature of 275°C for 2.5 h, after the reaction is completed, the melt is discharged by nitrogen, water-cooled, and pelletized, to obtain copolyether ester chips.

[0144] (2) Preparation of polyester-polyamide composite ultrafine fibers:

[0145] (2.1) Copolyether ester chips and polyamide chips are selected, wherein the intrinsic viscosity of the copolyether ester chips is 0.74 dl / g, and the relative viscosity of the polyamide chips is 2.80 dl / g.

[0146] (2.2) The two kinds of chips are drum-dried and then fed into screw extruders for melt extrusion, the screw temperature of the copolyether ester chips is 285°C / 295°C / 310°C / 300°C, and the screw temperature of the polyamide chips is 260°C / 265°C / 280°C / 270°C.

[0147] (2.3) The two kinds of melts obtained are introduced into a composite spinning assembly through metering pumps, the metering ratio of the copolyether ester component and the polyamide component is 65:35 during spinning, the spinning box temperature of the copolyether ester is 295°C, the spinning box temperature of the polyamide is 270°C, and an orange segment type spinneret is used in the composite spinning assembly. The two kinds of melts form streams at the spinneret and are extruded from the spinneret holes, and then are cooled and formed into a composite yarn through side blowing, the side blowing temperature is 22°C, the side blowing speed is 0.50 m / s, and the side blowing humidity is 75%, to obtain a composite yarn.

[0148] (2.4) The composite yarn is fed into a spinning duct for oiling, and then is drawn and heat set through a first hot roller and a second hot roller, the first hot roller temperature is 80°C, the second hot roller temperature is 150°C, the draw ratio is 2.8, and finally winding is performed at a winding speed of 4000 m / min, to obtain polyester-polyamide composite ultrafine fibers.

[0149] The polyester-polyamide composite ultrafine fibers prepared in this example have the following properties: the breaking strength is 2.85 cN / dtex, the breaking elongation is 39.04%, and the boiling water shrinkage is 15%.

[0150] (3) Weaving and fibrillation treatment of the composite fabric:

[0151] (3.1) After the polyester-polyamide composite ultrafine fiber warp yarn and the polyester-polyamide composite ultrafine fiber weft yarn are sized (sized with starch), weaving is performed, and the fabric structure is three over one twill (as shown in Figure 3 Figure), the warp density is 330 yarns / 10 cm, and the weft density is 270 yarns / 10 cm.

[0152] (3.2) Desizing: hot water washing (75℃, 10 min), immersion in a working solution (the working solution contains amylase, 80℃, 30 min), hot water washing, and cold water washing.

[0153] (3.3) Fabric cleaning: unrolling and water washing (containing oil removing agent CL911 g / L), clean water washing, and obtaining the fabric.

[0154] (3.4) Dyeing and fiber opening: a high-temperature and high-pressure overflow cylinder is used, and the dyeing solution formula is as follows: disperse dye S-3BG blue (the amount is 0.5% of the weight of the fabric), disperse uniformizing agent leveling agent XPO-5 (the content in the dyeing solution is 1 g / L), the solvent is water, and the bath ratio is 1:10. The dyeing solution is heated to 30℃, and the pH is adjusted to 4 by glacial acetic acid; the fabric is first run in the machine for 5 min, then the stirred dyeing solution is injected into the feeding barrel, slowly injected, and then heated to 110℃ at a rate of 1℃ / min, kept for 40 min, and then cooled to 70℃ at a rate of 0.5℃ / min. It is measured that the weight loss rate after fiber opening is 3.2%, the fiber opening rate is 97%, and the dyeing rate is 98%.

[0155] (3.5) Fixing, the temperature is 170℃, and the speed is 50 m / min.

[0156] (3.6) Product inspection.

[0157] Data analysis: compared with Example 2, the breaking strength of the polyester-polyamide composite ultrafine fiber of Example 6 is obviously reduced. It is illustrated that when the content of the polytetrahydrofuran soft segment in the copolyether ester is increased, the strength of the polyester-polyamide composite ultrafine fiber is reduced.

[0158] The above is only a preferred embodiment of the present application, and does not limit the present application in any way. Any simple modification, change, and equivalent transformation of the above embodiment according to the technical essence of the present application still belongs to the protection scope of the technical solution of the present application.

Claims

1. A method for improving the opening rate of polyester-polyamide composite fabric under the action of organic acid, characterized in that, The method comprises the following steps: (1) preparation of polyester-polyamide composite superfine fiber: copolyether ester and polyamide are used to prepare polyester-polyamide composite superfine fiber; the copolyether ester is a block copolymer composed of soft segments and hard segments, wherein the total chain length of all soft segments accounts for 40-50% of the entire chain length of the copolyether ester, the soft segment is polytetrahydrofuran, and the hard segment is polyethylene terephthalate; (2) weaving and fibrillation treatment of the composite fabric: the polyester-polyamide composite superfine fiber is woven into a fabric, and then subjected to organic acid solution treatment for fibrillation to obtain an acid fibrillation polyester-polyamide composite fabric; the organic acid solution treatment for fibrillation is performed together with dyeing, and the specific process comprises: immersing the fabric in a dyeing solution containing an organic acid and performing heat treatment; the organic acid is glacial acetic acid.

2. The method of claim 1, wherein, In step (1), the weight average molecular weight of the soft segment in the copolyether ester is 1000-3000 g / mol.

3. The method of claim 2, wherein, In step (1), the weight average molecular weight of the soft segment in the copolyether ester is 1500 g / mol.

4. The method of claim 1, wherein, In step (2), the pH of the acid solution is controlled to be 4-5 during the organic acid solution treatment for fibrillation.

5. The method of claim 1 or 3, wherein, In step (2), the temperature is 110-125 ℃ and the time is 40-50 min during the organic acid solution treatment for fibrillation.

6. The method of claim 1, wherein, In step (1), the mass ratio of the copolyether ester to the polyamide is 70:30-60:

40.

7. The method of claim 1, wherein, In step (1), the mass ratio of the copolyether ester to the polyamide is 65:

35.

8. The method of claim 1, wherein, In step (1), the intrinsic viscosity of the copolyether ester is 0.50-1.20 dl / g.

9. The method of claim 1, wherein, In step (1), the relative viscosity of the polyamide is 2.40-3.30 dl / g.

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