Warm-keeping spandex fabric and preparation method thereof

Abstract

The invention relates to a warm-keeping spandex fabric and a preparation method thereof. The fabric can be prepared by the following method: firstly, preparing an n-eicosane / polyurethane microcapsule phase change material; then, the n-eicosane / polyurethane microcapsule phase change material and polyurethane particles are blended, and polyurethane particles containing microcapsules are prepared; finally, spinning is conducted through a melt spinning machine, the silk threads are woven into the fabric, and the fabric is the warm-keeping spandex fabric. The air permeability range of the spandex fabric prepared by the method is between 968.7 mm / s and 981.5 mm / s, and the crow value range of the spandex fabric is between 0.86 mm / s and 0.88 mm / s, which shows that the spandex fabric prepared by the method has better warm-keeping performance on the premise of not influencing the air permeability.

Description

Technical Field

[0001] This invention belongs to the field of fabric preparation technology, specifically relating to a warm spandex fabric and its preparation method. Background Technology

[0002] Modern people have increasingly higher requirements for the comfort, functionality, and aesthetics of clothing. Traditional thermal insulation materials are generally bulky, inconvenient for movement, and lack aesthetic appeal. For people working in extremely low-temperature environments, passive insulation cannot adequately meet the functional requirements of clothing. Therefore, the development of new thermal insulation materials is of great significance.

[0003] Spandex, a polyurethane elastic fiber, is a key factor in improving fabric quality, and its application in fabrics is constantly expanding, with its content continuously increasing. Compared to natural fibers, chemical fibers have many advantages. Through modification, chemical fibers can acquire numerous functions that natural fibers cannot match. A type of spandex fiber with heat-retaining properties not only enhances fabric comfort but, more importantly, reduces heat loss from the body, making people feel warm and comfortable in the cold winter.

[0004] Literature review indicates that the warmth-retaining properties of spandex fabrics have attracted attention. For example, Chinese invention patent application number 201410576731.0 discloses a method for preparing a warm spandex fiber: a prepolymer is manufactured according to the specified formula, chain-extended using a chain extender (N,N-dimethylacetamide solution in water), and a fiber-forming polymer is obtained after the reaction. This polymer is then mixed with additive sizing agents and stored for maturation. During the maturation process, a supercritical carbon dioxide system is established to obtain the spinning solution. The warm spandex fiber is then obtained using dry spinning equipment and processes. Currently, the dry spinning technology for spandex mainly uses diamine chain extension, which results in high manufacturing costs, a problem that urgently needs to be addressed. Furthermore, under existing process conditions, it is difficult to increase the concentration of the spinning solution, otherwise poor dissolution will occur, severely affecting spinnability. Additionally, the large solvent consumption leads to high energy consumption and high costs. Therefore, it is necessary to develop a new technology for producing warm spandex fabrics while overcoming the technical difficulties in the manufacturing process to meet the needs of spandex fabric manufacturing technology and the apparel industry. Summary of the Invention

[0005] In view of the above-mentioned drawbacks of the existing technology, the purpose of this invention is to provide a warm spandex fabric and its preparation method.

[0006] The purpose of this invention is to provide a warm spandex fabric with features such as heat retention and environmental friendliness. This fabric can be prepared by the following method: First, an eicosane / polyurethane microcapsule phase change material is prepared; then, the eicosane / polyurethane microcapsule phase change material is blended with polyurethane particles to obtain polyurethane particles containing microcapsules; finally, the particles are spun using a melt spinning machine to weave the yarn into a fabric, which is the warm spandex fabric.

[0007] The objective of this invention is achieved through the following technical solution: A method for preparing a warm spandex fabric includes the following steps: (1) Preparation of n-eicosane / polyurethane microcapsule phase change material: In a constant temperature water bath, n-eicosane and toluene-2,4-diisocyanate (TDI) were dissolved in cyclohexane to obtain an organic phase; Tween 80 was dissolved in water to obtain an aqueous phase; the organic phase was added dropwise to the aqueous phase under stirring to emulsify and form an O / W emulsion; an aqueous solution containing ethylene glycol was added dropwise to the emulsion and the reaction was stirred; after the reaction was complete, the product was washed, filtered and dried to obtain n-eicosane / polyurethane microcapsule phase change material.

[0008] Preferably, the temperature of the constant temperature water bath is 30–40°C.

[0009] Preferably, the ratio of n-eicosane, toluene-2,4-diisocyanate (TDI) and cyclohexane is 1 g : (1-2) mL : (40-60) mL.

[0010] Preferably, the ratio of the emulsifier Tween 80 to water is 1 g: (40-60) mL.

[0011] Preferably, the organic phase is added to the aqueous phase over a period of 20 to 40 minutes.

[0012] Preferably, the ratio of the organic phase to the aqueous phase is 1:(4-6).

[0013] Preferably, the volume fraction of ethylene glycol in the aqueous solution containing ethylene glycol is 5-10%.

[0014] Preferably, the ratio of the emulsion to the aqueous solution containing ethylene glycol is 1:(0.1 to 0.3).

[0015] Preferably, the temperature of the stirring reaction is 50–70°C, and the time is 1–3 hours.

[0016] (2) Blending and granulation: The n-eicosane / polyurethane microcapsule phase change material obtained in step (1) is blended with polyurethane particles by granulation using a screw extruder to obtain polyurethane particles containing microcapsules.

[0017] Preferably, the ratio of the amount of n-eicosane / polyurethane microcapsule phase change material obtained in step (1) to that of polyurethane is 1: (300-500).

[0018] (3) Melt spinning and fabric preparation: The polyurethane particles containing microcapsules obtained in step (2) are spun by a melt spinning machine, and the yarn is woven into a fabric, which is a warm spandex fabric.

[0019] This invention employs interfacial polymerization to prepare microcapsules. First, two monomers containing multiple functional groups are dissolved separately in two immiscible phase change material (PCM) emulsion systems using a water-organic solvent emulsion system. During the polymerization reaction, toluene-2,4-diisocyanate and ethylene glycol migrate from the dispersed phase (PCM) and the continuous phase, respectively, to the interface and rapidly polymerize at the interface. This achieves a rapid reaction between toluene-2,4-diisocyanate and ethylene glycol at the droplet interface, forming a microcapsule encapsulation layer. The resulting polymer film encapsulates the PCM n-eicosane to form microcapsules.

[0020] This invention has the following significant features: (1) The present invention uses polyurethane as the wall material and n-eicosane as the core material to prepare n-eicosane / polyurethane microcapsule phase change material by interfacial polymerization.

[0021] (2) The organic phase change material n-eicosane has advantages such as high latent heat of phase change, non-flammability, and low cost, and it has a promising future in the field of thermal insulation fabrics. However, n-eicosane also has disadvantages such as easy leakage, so it needs to be encapsulated when used. The applicant of this invention unexpectedly discovered that n-eicosane can be used as the core material of microcapsule phase change materials. When applied to polyurethane fibers, the microcapsule phase change material can effectively overcome the problem of easy leakage of n-eicosane. Since the wall material of the microcapsule phase change material is polyurethane, the microcapsule phase change material has very good compatibility with polyurethane particles.

[0022] (3) The raw materials for the warm spandex fabric prepared by the present invention are widely available, the preparation process is simple, and it has a good market promotion prospect.

[0023] (4) The thermal insulation performance of the spandex fabric prepared by the present invention was not significantly weakened after 10 washes, which indicates that the n-eicosane / polyurethane microcapsule phase change material was well sealed and preserved in the fabric and was not leaked.

[0024] (5) The air permeability of the spandex fabric prepared by the present invention ranges from 968.7 to 981.5 mm / s, and the clo value of the spandex fabric prepared by the present invention ranges from 0.86 to 0.88, which is significantly higher than the clo value of spandex fabrics on the market that have not undergone thermal insulation treatment. After 10 washes, the clo value of the fabric did not decrease significantly, which indicates that the spandex fabric prepared by the present invention has good thermal insulation performance without affecting the air permeability. Detailed Implementation

[0025] The present invention is described in detail below with reference to the embodiments and comparative examples.

[0026] Example 1 In this embodiment, a warm spandex fabric is prepared by the following method, including the following steps: (1) Preparation of n-eicosane / polyurethane microcapsule phase change material: In a constant temperature water bath at 35℃, 1g of n-eicosane and 1.5mL of toluene-2,4-diisocyanate (TDI) were dissolved in 50mL of cyclohexane to obtain an organic phase; 1g of emulsifier Tween 80 was dissolved in 50mL of water to obtain an aqueous phase; 10mL of the organic phase was added dropwise to 50mL of the aqueous phase under stirring for 30min to emulsify and form an O / W emulsion; 12mL of 7.5% ethylene glycol aqueous solution was added dropwise to the emulsion, and the reaction was stirred at 60℃ for 2h; after the reaction was complete, the product was washed, filtered, and dried to obtain the n-eicosane / polyurethane microcapsule phase change material.

[0027] (2) Blending and granulation: 1g of the n-eicosane / polyurethane microcapsule phase change material obtained in step (1) is blended with 400g of polyurethane particles by granulation through a screw extruder to obtain polyurethane particles containing microcapsules.

[0028] (3) Melt spinning and fabric preparation: The polyurethane particles containing microcapsules obtained in step (2) are spun by a melt spinning machine, and the yarn is woven into a fabric, which is a warm spandex fabric a.

[0029] Example 2 In this embodiment, a warm spandex fabric is prepared by the following method, including the following steps: (1) Preparation of n-eicosane / polyurethane microcapsule phase change material: In a constant temperature water bath at 30℃, 1g of n-eicosane and 1.0mL of toluene-2,4-diisocyanate (TDI) were dissolved in 40mL of cyclohexane to obtain an organic phase; 1g of emulsifier Tween 80 was dissolved in 40mL of water to obtain an aqueous phase; 10mL of the organic phase was added dropwise to 40mL of the aqueous phase under stirring for 20min to emulsify and form an O / W emulsion; 5mL of 5% ethylene glycol aqueous solution was added dropwise to the emulsion, and the reaction was stirred at 50℃ for 1h; after the reaction was complete, the product was washed, filtered, and dried to obtain the n-eicosane / polyurethane microcapsule phase change material.

[0030] (2) Blending and granulation: 1g of the n-eicosane / polyurethane microcapsule phase change material obtained in step (1) is blended with 300g of polyurethane particles by granulation through a screw extruder to obtain polyurethane particles containing microcapsules.

[0031] (3) Melt spinning and fabric preparation: The polyurethane particles containing microcapsules obtained in step (2) are spun by a melt spinning machine, and the filaments are woven into fabric, which is the warm spandex fabric b.

[0032] Example 3 In this embodiment, a warm spandex fabric is prepared by the following method, including the following steps: (1) Preparation of n-eicosane / polyurethane microcapsule phase change material: In a constant temperature water bath at 40℃, 1g of n-eicosane and 2mL of toluene-2,4-diisocyanate (TDI) were dissolved in 60mL of cyclohexane to obtain an organic phase; 1g of emulsifier Tween 80 was dissolved in 60mL of water to obtain an aqueous phase; 10mL of the organic phase was added dropwise to 60mL of the aqueous phase under stirring for 40min to emulsify and form an O / W emulsion; 21mL of 10% ethylene glycol aqueous solution was added dropwise to the emulsion, and the reaction was stirred at 70℃ for 3h; after the reaction was complete, the product was washed, filtered, and dried to obtain the n-eicosane / polyurethane microcapsule phase change material.

[0033] (2) Blending and granulation: 1g of the n-eicosane / polyurethane microcapsule phase change material obtained in step (1) is blended with 500g of polyurethane particles by granulation through a screw extruder to obtain polyurethane particles containing microcapsules.

[0034] (3) Melt spinning and fabric preparation: The polyurethane particles containing microcapsules obtained in step (2) are spun by a melt spinning machine, and the threads are woven into fabric, which is a warm spandex fabric c.

[0035] Comparative Example A Compared with Example 1, in this example, the type of core material is changed, that is, "eicosane" in step (1) is changed to "eicosane", and other preparation methods are carried out according to the preparation method of Example 1 to obtain spandex fabric d.

[0036] Comparative Example B Compared with Example 1, in this example, the type of solvent is changed, that is, "cyclohexane" in step (1) is changed to "dichloromethane", and other preparation methods are carried out according to the preparation method of Example 1 to obtain spandex fabric e.

[0037] Comparative Example C Compared with Example 1, in this example, the amount of microcapsules was changed, that is, "1g of n-eicosane / polyurethane microcapsule phase change material prepared in step (1)" in step (2) was changed to "0.01g of n-eicosane / polyurethane microcapsule phase change material prepared in step (1)". Other preparation methods were carried out according to the preparation method of Example 1, and spandex fabric f was obtained.

[0038] Breathability test: To better test the air permeability of the spandex fabric prepared in this invention, spandex fabrics a, b, c, d, e, and f prepared in the specific embodiments 1-3 and comparative examples A-C of this invention, as well as unfinished spandex fabric (purchased from the market), were selected; the fabric usage was selected as 300 g / m². 2 The air permeability was tested according to GB / T5453-1997, with a sample size of 20mm × 22mm and a pressure of 100 Pa. The test temperature was (20±2)℃ and the humidity was (65±2)%. The test principle is to measure the airflow rate passing vertically through a given area of ​​the sample within a certain time under specified pressure difference conditions, and calculate the air permeability R according to the following formula.

[0039] ; In the formula: qv The average airflow rate, A The area is the test area, and 167 is the conversion factor. The fabric to be tested was washed according to the standard washing method. The air permeability of the initial sample and the sample after 10 washes were tested. The test results are shown in Table 1.

[0040] Table 1. Air permeability of spandex fabrics a, b, c, d, e, f and unfinished spandex fabrics ; As shown in Table 1, the air permeability of spandex fabrics a, b, and c ranges from 968.7 to 981.5 mm / s, which is within the normal range. After 10 washes, the air permeability of fabrics a, b, and c did not increase significantly. Therefore, it can be concluded that the spandex fabric prepared in this invention has good air permeability. The air permeability of spandex fabrics d, e, and f prepared in comparative example AC also showed good performance, indicating that the type of core material, the type of solvent, and the amount of microcapsules have little impact on the air permeability of spandex fabrics.

[0041] Warmth retention test: To better test the warmth retention of the spandex fabric prepared in this invention, spandex fabrics a, b, c, d, e, and f prepared in the specific embodiments 1-3 and comparative examples A-C, as well as unfinished spandex fabric (purchased from the market), were selected. The warmth retention of the materials was tested according to GB / T11048-2008-T "Determination of Thermal and Moisture Resistance under Steady-State Conditions for Physiological Comfort of Textiles". Before testing, the samples were pre-conditioned and conditioned according to GB6529-86 "Standard for Atmospheric Environment of Constant Temperature and Humidity Chamber". The samples were conditioned in a constant temperature and humidity chamber for 24 h at a temperature of (20 ± 2) ℃ and a humidity of (65 ± 2)%. The sample size was 300 mm × 300 mm, and the preheating time was 15 minutes. The fabrics were washed according to the standard washing method, and the warmth retention performance of the initial samples and the samples after 10 washes was tested. The test results are shown in Table 2.

[0042] Table 2. Thermal performance of spandex fabrics a, b, c, d, e, f and unfinished spandex fabrics. ; As shown in Table 2, the clo value of spandex fabrics a, b, and c ranges from 0.86 to 0.88, which is higher than that of untreated spandex fabric. After 10 washes, the clo value of fabrics a, b, and c did not decrease significantly. A higher clo value indicates better warmth retention. Therefore, it can be concluded that the spandex fabric prepared in this invention has good warmth retention performance. The warmth retention performance of spandex fabrics d, e, and f prepared in Comparative Example AC is slightly worse than that of fabrics a, b, and c. This indicates that the type of core material, the type of solvent, and the amount of microcapsules all have a significant impact on the warmth retention performance of spandex fabrics.

[0043] Comprehensive analysis suggests that the spandex fabric prepared by this invention has good warmth retention performance without affecting breathability.

Claims

1. A method for preparing a warm spandex fabric, characterized in that, The preparation method includes the following steps: (1) Preparation of n-eicosane / polyurethane microcapsule phase change material: In a constant temperature water bath, n-eicosane and toluene-2,4-diisocyanate were dissolved in cyclohexane to obtain an organic phase; Tween 80 emulsifier was dissolved in water to obtain an aqueous phase; the organic phase was added dropwise to the aqueous phase under stirring to emulsify and form an O / W emulsion; an aqueous solution containing ethylene glycol was added dropwise to the emulsion and the reaction was stirred; after the reaction was complete, the product was washed, filtered and dried to obtain n-eicosane / polyurethane microcapsule phase change material; (2) Blending and granulation: The n-eicosane / polyurethane microcapsule phase change material obtained in step (1) is blended with polyurethane particles by granulation using a screw extruder to obtain polyurethane particles containing microcapsules. (3) Melt spinning and fabric preparation: The polyurethane particles containing microcapsules obtained in step (2) are spun by a melt spinning machine, and the yarn is woven into a fabric, which is a warm spandex fabric.

2. The method for preparing a warm spandex fabric according to claim 1, characterized in that, The ratio of n-eicosane, toluene-2,4-diisocyanate and cyclohexane used in step (1) is 1 g : (1-2) mL : (40-60) mL.

3. The method for preparing a warm spandex fabric according to claim 1, characterized in that, The organic phase in step (1) is added to the aqueous phase over a time of 20 to 40 minutes; the ratio of the organic phase to the aqueous phase is 1 mL: (4 to 6) mL.

4. The method for preparing a warm spandex fabric according to claim 1, characterized in that, The ratio of emulsifier Tween 80 to water in step (1) is 1 g: (40-60) mL.

5. The method for preparing a warm spandex fabric according to claim 1, characterized in that, In step (1), the volume fraction of ethylene glycol in the aqueous solution containing ethylene glycol is 5-10%; the ratio of the emulsion to the aqueous solution containing ethylene glycol is 1 mL: (0.1-0.3) mL.

6. The method for preparing a warm spandex fabric according to claim 1, characterized in that, The temperature of the constant temperature water bath in step (1) is 30-40℃; the temperature of the stirring reaction is 50-70℃ and the time is 1-3h.

7. The method for preparing a warm spandex fabric according to claim 1, characterized in that, In step (2), the ratio of the amount of n-eicosane / polyurethane microcapsule phase change material obtained in step (1) to the amount of polyurethane is 1 g: (300-500) g.

8. A warm spandex fabric, characterized in that, It is prepared by the method described in any one of claims 1 to 7.