Bionic breathable composite material based on microporous nanofiber membrane

Abstract

The invention relates to the technical field of layered composite fabrics, in particular to a bionic breathable composite material based on a microporous nanofiber membrane. The composite material comprises a base cloth layer and two polyurethane grain surface layers, polyurethane is prepared from polyol, diisocyanate, a chain extender, a catalyst and a functional filler as raw materials, the polyurethane is prepared into a spinning solution, the spinning solution sequentially forms microporous nanofiber membranes on the surfaces of the two sides of leather base cloth through an electrostatic spinning process, and the microporous nanofiber membranes and the polyurethane grain surface layers are bonded to form the composite material. As the polyurethane grain surface layer, the microporous nanofiber membrane not only can achieve the effect of imitated leather, but also has good air permeability; due to introduction of the hydrophobic raw material, the waterproof performance of the polyurethane grain surface layer can be improved, water can be prevented from entering, and the situation that the air permeability of the composite material is affected due to hole blocking caused by swelling of the polyurethane after water absorption can be prevented; the introduction of hydrophobic groups in the chain extender can further improve the waterproof performance of polyurethane, and the introduction of cationic groups can improve the color fastness of the composite material.

Description

Technical Field

[0001] The present invention relates to the technical field of layered composite fabrics, and in particular to a bionic breathable composite material based on a microporous nanofiber membrane. Background Art

[0002] Genuine leather fabric is to take animal hide as raw material, is processed through the operation such as tanning, has the characteristics such as breathable, soft, wear-resistant, warmth-keeping, is deeply loved.But, due to the high cost of raw materials, expensive, and widely used is restricted.Synthetic leather is a kind of as imitation leather material, can approach the texture of genuine leather, and with low cost, good waterproofness, especially microfiber leather, obtains common application.Microfiber leather adopts microfiber (usually terylene or nylon) and polyurethane composite to make, has the characteristics such as soft and delicate hand feel, wear resistance height.In the prior art, adopting microfiber leather base cloth is immersed in polyurethane solution more, or is coated with polyurethane solution, also forms polyurethane film layer and prepares microfiber leather, but continuous film layer can affect the air permeability of microfiber leather.

[0003] Chinese patent application CN119392494A discloses a method for preparing microporous, moisture-heat migration-resistant microfiber synthetic leather based on waterborne polyurethane. The method involves immersing a microfiber leather base fabric in a nano-waterborne polyurethane solution and padding it to produce the microfiber synthetic leather. During the preparation process, nano-SiO2 is doped into the aqueous polyurethane solution, and then an alkali solution reacts with the SiO2 to form pores to improve the breathability of the microfiber synthetic leather. However, this method suffers from uneven pore formation caused by the uneven doping of the SiO2 with the polyurethane solution. Furthermore, polyurethane, particularly polyester-type polyurethane, has poor alkali resistance and is susceptible to molecular chain breakage and strength loss under the action of alkali solution. Chinese patent application CN112430911B discloses a method for preparing a nanofiber biomimetic membrane with a simulated leather grain surface layer. Using an electrospinning process, polyurethane is applied to the surface of a second leather layer to form a membrane layer with a nanofiber network structure, addressing the problem of a missing second leather grain surface layer. However, the molecular structure and performance characteristics of the polyurethane are not disclosed, making it impossible to predict its waterproof properties and dyeing effect. If the polyurethane film layer is not waterproof, on the one hand, water will penetrate into the material; on the other hand, if the polyurethane absorbs water and swells, it will cause pore blockage and reduce air permeability. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention provides a bionic breathable composite material based on a microporous nanofiber membrane to solve the problem that the air permeability and waterproofness of synthetic leather materials in the existing technology need to be improved.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A biomimetic breathable composite material based on a microporous nanofiber membrane, comprising a base fabric layer and two polyurethane grain layers;

[0007] The two polyurethane grain layers are respectively located on both sides of the base fabric layer;

[0008] The bionic breathable composite material of the microporous nanofiber membrane is prepared by the following steps:

[0009] Step 1: mixing and reacting polyol, diisocyanate, chain extender, catalyst and functional filler to prepare polyurethane;

[0010] Step 2: dissolving polyurethane in an organic solvent to obtain a spinning solution;

[0011] Step 3: Using the leather base fabric as a receiver, the spinning solution is used to form microporous nanofiber membranes on both sides of the leather base fabric through an electrospinning process to obtain a biomimetic breathable composite material based on the microporous nanofiber membrane;

[0012] In the bionic breathable composite material based on microporous nanofiber membranes, the leather base fabric is the base fabric layer, and the microporous nanofiber membranes on both sides of the leather base fabric are two polyurethane grain layers.

[0013] Preferably, the step 1 specifically includes:

[0014] The polyol, diisocyanate, chain extender, catalyst and functional filler are mixed and uniformly mixed, and then the mixture is extruded through a twin-screw extruder, granulated and dried to obtain polyurethane;

[0015] Wherein, the weight ratio of the polyol, diisocyanate, chain extender, catalyst and functional filler is (90-100):(8-16):(6-10):(0.05-0.1):(2-4);

[0016] The reaction temperature is 170-190°C.

[0017] Preferably, the polyol comprises polyester polyol, perfluoropolyether diol and hydroxyl-terminated polydimethylsiloxane (hydroxy silicone oil);

[0018] The mass ratio of polyester polyol, perfluoropolyether diol and hydroxyl-terminated polydimethylsiloxane is (80-100):(15-25):(20-30).

[0019] Preferably, the polyester polyol comprises polycaprolactone diol (PCL).

[0020] Preferably, the diisocyanate comprises isophorone diisocyanate.

[0021] Preferably, the chain extender comprises dodecyl bis(hydroxyethyl)methylammonium chloride.

[0022] Preselectively, the catalyst comprises dibutyltin dilaurate.

[0023] Preferably, the functional filler comprises surface-modified hydrophobic silica.

[0024] Preferably, the surface-modified hydrophobic silica is prepared by the following steps: adding hydrophobic silica to an ethanol aqueous solution, adjusting the pH value to 4-5, ultrasonically dispersing, adding N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, reacting, filtering, washing, and drying after the reaction to obtain the surface-modified hydrophobic silica.

[0025] Preferably, the mass ratio of hydrophobic silica, ethanol aqueous solution, and N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane is 10:(250-350):(2-4), and the reaction conditions are 65-75° C. for 8-12 hours.

[0026] Furthermore, the ethanol aqueous solution includes 75 wt% ethanol aqueous solution.

[0027] Preferably, in step 2, the mass ratio of polyurethane to organic solvent in the spinning solution is 1:(4.5-5.5), and the dissolution condition is stirring at a temperature of 35-45° C. until the polyurethane is completely dissolved.

[0028] Preferably, the organic solvent comprises N,N-dimethylformamide.

[0029] Preferably, in step 3, the leather base fabric comprises a needle-punched microfiber non-woven fabric;

[0030] The process parameters of electrospinning include: spinning environment humidity of 50±2% RH, spinning solution extrusion rate of 0.5-1 mL / h, positive voltage of 25-30 kV, negative voltage of 5 kV, and receiving distance of 10-20 cm.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The biomimetic breathable composite material based on microporous nanofiber membrane in the present invention is a synthetic leather material, comprising a base fabric layer and two polyurethane grain layers; a needle-punched microfiber non-woven fabric is used as the leather base fabric, and microporous nanofiber membranes are sequentially formed on both sides of the needle-punched microfiber non-woven fabric through an electrospinning process. The resulting composite material can achieve the effect of imitating leather. The presence of the microporous structure makes the composite material have excellent breathability compared to the polyurethane grain layer formed by impregnation or coating;

[0033] The main raw materials for preparing the polyurethane in the present invention are polyols, diisocyanates, chain extenders, and functional fillers. Among them, the polyols include polyester polyols, perfluoropolyether diols, and hydroxyl-terminated polydimethylsiloxane. Compared with the hydrophilic polyether polyols, the polyurethane prepared using the hydrophobic polyester polyols has better water resistance. The fluorine element and silicone introduced by the perfluoropolyether diols and hydroxyl-terminated polydimethylsiloxane can also effectively improve the water resistance of the polyurethane. The addition of surface-modified hydrophobic silica as a functional filler can also improve the water resistance of the polyurethane.

[0034] Using dodecyl bis(hydroxyethyl)methylammonium chloride as a chain extender can not only extend the polyurethane molecular chain by diffusion and adjust the hard segment structure, thereby improving the performance of the polyurethane, but the hydrocarbon chain introduced into its molecule is a hydrophobic group, which can further improve the waterproof performance of the polyurethane. In addition, the cationic group quaternary ammonium salt introduced into its molecule can combine with reactive dyes containing anionic groups (carboxyl, sulfonic acid, etc.) to form salts, thereby improving color fastness. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a scanning electron microscope image of the microporous nanofiber membrane prepared in Example 1 of the present invention;

[0036] Figure 2 It is a line graph showing the waterproof performance test results of the bionic breathable composite materials based on microporous nanofiber membranes prepared in Examples 2-6 of the present invention and Comparative Examples 1-3. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment discloses a method for preparing a microporous nanofiber membrane, comprising the following steps:

[0040] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 170° C., pelletizing at 10° C., and drying at 50° C. to obtain a polyurethane;

[0041] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 62.6:11.7:15.7:8:6:0.05:2;

[0042] The surface-modified hydrophobic silica is prepared by the following steps:

[0043] The hydrophobic silica was added to a 75 wt % ethanol aqueous solution, the pH value was adjusted to 4.5 with 1 mol / L hydrochloric acid, and after ultrasonic dispersion at a frequency of 50 kHz for 30 min, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane was added dropwise, and the mass ratio of hydrophobic silica, 75 wt % ethanol aqueous solution, and N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane was 10:300:3. The mixture was reacted at a temperature of 70° C. for 10 h. After the reaction was completed, the mixture was filtered, washed with ethanol three times, and dried in a vacuum drying oven at 50° C. to constant weight to obtain surface-modified hydrophobic silica;

[0044] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:4.5, stirring at 35° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0045] Step 3: Using aluminum foil as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed by electrospinning, which was then dried in a vacuum drying oven at 50°C for 10 hours to obtain a microporous nanofiber membrane.

[0046] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the extrusion rate of the spinning solution is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0047] Example 2

[0048] This embodiment discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0049] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 170° C., pelletizing at 10° C., and drying at 50° C. to obtain a polyurethane;

[0050] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 62.6:11.7:15.7:8:6:0.05:2;

[0051] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0052] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:4.5, stirring at 35° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0053] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0054] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0055] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0056] Example 3

[0057] This embodiment discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0058] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 190° C., pelletized at 10° C., and dried at 50° C. to obtain a polyurethane;

[0059] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 64.5:16.1:19.4:16:10:0.1:4;

[0060] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0061] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:5.5, stirring at 45° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0062] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0063] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0064] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0065] Example 4

[0066] This embodiment discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0067] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 180° C., pelletizing at 10° C., and drying at 50° C. to obtain a polyurethane;

[0068] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 63.2:13.4:16.4:10:7:0.06:2.5;

[0069] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0070] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:5, stirring at 45°C until the polyurethane is completely dissolved to obtain a spinning solution;

[0071] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0072] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0073] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0074] Example 5

[0075] This embodiment discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0076] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 180° C., pelletizing at 10° C., and drying at 50° C. to obtain a polyurethane;

[0077] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecyl bis (hydroxyethyl) methyl ammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 63.3:14.1:17.6:12:8:0.07:3;

[0078] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0079] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:5, stirring at 45°C until the polyurethane is completely dissolved to obtain a spinning solution;

[0080] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0081] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0082] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0083] Example 6

[0084] This embodiment discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0085] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 180° C., pelletizing at 10° C., and drying at 50° C. to obtain a polyurethane;

[0086] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecylbis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and surface-modified hydrophobic silica is 64.2:14.9:18.9:14:9:0.08:3.5;

[0087] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0088] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:5, stirring at 45°C until the polyurethane is completely dissolved to obtain a spinning solution;

[0089] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0090] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0091] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0092] Comparative Example 1

[0093] This comparative example discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0094] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecyl bis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 170° C., granulation at 10° C., and drying at 50° C. to obtain a polyurethane;

[0095] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, dodecyl bis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and hydrophobic silica is 62.6:11.7:15.7:8:3:0.05:1.8;

[0096] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:4.5, stirring at 35° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0097] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0098] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0099] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0100] Comparative Example 2

[0101] This comparative example discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0102] Step 1: polycaprolactone diol, isophorone diisocyanate, dodecyl bis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and hydrophobic silica are mixed and uniformly mixed, and then extruded through a twin-screw extruder at 170° C., granulated at 10° C., and dried at 50° C. to obtain polyurethane;

[0103] The mass ratio of polycaprolactone diol, isophorone diisocyanate, dodecyl bis(hydroxyethyl)methylammonium chloride, dibutyltin dilaurate, and hydrophobic silica is 90:8:3:0.05:1.8.

[0104] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:4.5, stirring at 35° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0105] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0106] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0107] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0108] Comparative Example 3

[0109] This comparative example discloses a biomimetic breathable composite material based on a microporous nanofiber membrane, which is prepared by the following steps:

[0110] Step 1: polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, 1,4-butanediol, dibutyltin dilaurate, and surface-modified hydrophobic silica are mixed and uniformly mixed, followed by extrusion through a twin-screw extruder at 170° C., granulation at 10° C., and drying at 50° C. to obtain a polyurethane;

[0111] Among them, the mass ratio of polycaprolactone diol, perfluoropolyether diol, hydroxyl-terminated polydimethylsiloxane, isophorone diisocyanate, 1,4-butanediol, dibutyltin dilaurate, and surface-modified hydrophobic silica is 62.6:11.7:15.7:8:1.7:0.05:2;

[0112] The preparation method of the surface-modified hydrophobic silica is the same as that of Example 1;

[0113] Step 2: adding polyurethane to N,N-dimethylformamide at a mass ratio of polyurethane to N,N-dimethylformamide of 1:4.5, stirring at 35° C. until the polyurethane is completely dissolved to obtain a spinning solution;

[0114] Step 3: Using a needle-punched microfiber non-woven fabric as a receiver, the spinning solution was heated to 50°C, and a microporous nanofiber membrane was formed on one surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours. Then, a microporous nanofiber membrane was formed on the other surface of the needle-punched microfiber non-woven fabric by an electrospinning process, and then dried in a vacuum drying oven at 50°C for 10 hours to obtain a bionic breathable composite material based on a microporous nanofiber membrane.

[0115] The parameters of the electrospinning process are as follows: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.8 mL / h, the positive voltage is 25 kV, the negative voltage is 5 kV, and the receiving distance is 15 cm.

[0116] The bionic breathable composite material based on microporous nanofiber membrane includes a base fabric layer and two polyurethane grain layers; the needle-punched microfiber non-woven fabric serves as the base fabric layer, and the microporous nanofiber membranes on both sides of the needle-punched microfiber non-woven fabric are two polyurethane grain layers, and the thickness of the two polyurethane membrane layers is 50 μm.

[0117] In the above embodiments and comparative examples, polycaprolactone diol was purchased from Jiangsu Minglin Chemical Technology Co., Ltd., brand: PCL1000, molecular weight of 1000; perfluoropolyether diol was purchased from Wuhan Kemik Biopharmaceutical Technology Co., Ltd., appearance: colorless transparent liquid, molecular weight of 500; hydroxyl-terminated polydimethylsiloxane was purchased from Shandong Begbao New Materials Co., Ltd., appearance: colorless transparent liquid, molecular weight: 2000-3000, hydroxyl content: 8.5%-9.5%, viscosity: 25-30CTS; hydrophobic silica was purchased from Shijiazhuang Juou New Materials Technology Co., Ltd., particle size specification: 8000 mesh; needle-punched microfiber non-woven fabric was purchased from Suzhou Senhong Non-woven Fabric Co., Ltd., composition: polyester, gram weight: 180g / m 2 .

[0118] Test example

[0119] The performance tests of the biomimetic breathable composite materials based on microporous nanofiber membranes prepared in the examples and comparative examples were carried out:

[0120] (1) Waterproof performance: The static water contact angles of the polyurethane grain layers of the biomimetic breathable composite materials based on microporous nanofiber membranes prepared in Examples 2-6 and Comparative Examples 1-3 were measured with reference to the standard GB / T30693-2014 “Measurement of the contact angle of plastic films with water”. The measurement results are shown in Table 1:

[0121] Table 1

[0122]

[0123] As shown in Table 1, the biomimetic breathable composite material based on microporous nanofiber membranes prepared by the present invention exhibits excellent waterproof properties. First, the introduction of the fluorine-containing polyol perfluoropolyether diol and the silicone-containing polyol hydroxyl-terminated polydimethylsiloxane significantly enhances the polyurethane's waterproof properties. Second, the addition of hydrophobic silica improves the polyurethane's mechanical and waterproof properties. The amino groups introduced by the hydrophobic silica during modification react with isocyanate, achieving bonding with the polyurethane molecules. This improves the uniformity of its dispersion in the polyurethane spinning solution and enhances the polyurethane's waterproof properties. Finally, the hydrophobic hydrocarbon chains introduced into the chain extender, dodecylbis(hydroxyethyl)methylammonium chloride, further enhance the polyurethane's waterproof properties. Compared with Example 2, in Comparative Example 1, the hydrophobic silica has not been modified, the dispersion uniformity in the polyurethane spinning solution is poor, and the waterproof effect is slightly reduced; in Comparative Example 2, the polyol does not contain perfluoropolyether diol and hydroxyl-terminated polydimethylsiloxane, and the formed polyurethane does not contain fluorine element and silicone, and the waterproof performance is greatly reduced; in Comparative Example 2, the chain extender is replaced by dodecyl bis (hydroxyethyl) methyl ammonium chloride with 1,4-butanediol, which lacks the hydrophobic effect of the hydrocarbon chain and the waterproof performance is reduced.

[0124] (2) Dyeing performance: The biomimetic breathable composite materials based on microporous nanofiber membranes prepared in Examples 2-6 and Comparative Examples 1-3 were subjected to dyeing tests. The composite materials were immersed in a dye solution (1 wt% reactive brilliant red aqueous solution) for dyeing at a bath ratio of 1:10, a dyeing temperature of 90°C, and a dyeing time of 2 h. After dyeing, the composite materials were dried at 100°C and then baked at 140°C for 5 min. The wet rubbing fastness of the dyed composite materials was measured with reference to the standard GB / T3920-2008 "Textiles - Tests for Colour Fastness - Colour Fastness to Rubbing". The test results are shown in Table 2:

[0125] Table 2

[0126]

[0127] As shown in Table 2, the biomimetic breathable composite material based on microporous nanofiber membrane prepared by the present invention has good dyeing properties. First, the hydrophobic silica is modified to introduce amino groups, which makes the polyurethane have dyeing ability. Secondly, the cationic group quaternary ammonium salt introduced into the chain extender dodecyl bis hydroxyethyl methyl ammonium chloride molecule can be combined with the anionic groups (carboxyl, sulfonic acid, etc.) in the reactive dye molecules to form salts, thereby improving the color fastness. Compared with Example 2, in Comparative Examples 1 and 2, the hydrophobic silica was not modified to introduce amino groups, and the dyeing performance was slightly reduced; in Comparative Example 3, the chain extender was replaced by 1,4-butanediol by dodecyl bis hydroxyethyl methyl ammonium chloride, which lacked the cationic effect of the quaternary ammonium salt, and the wet friction fastness of the composite material decreased.

[0128] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A biomimetic breathable composite material based on microporous nanofiber membrane, characterized in that: It includes a base fabric layer and two polyurethane grain layers; The two polyurethane grain layers are respectively located on both sides of the base fabric layer; The bionic breathable composite material of the microporous nanofiber membrane is prepared by the following steps: Step 1: mixing and reacting polyol, diisocyanate, chain extender, catalyst and functional filler to prepare polyurethane; Step 2: dissolving polyurethane in an organic solvent to obtain a spinning solution; Step 3: Using the leather base fabric as a receiver, the spinning solution is used to form microporous nanofiber membranes on both sides of the leather base fabric through an electrospinning process to obtain a biomimetic breathable composite material based on the microporous nanofiber membrane; In the bionic breathable composite material based on microporous nanofiber membranes, the leather base fabric is the base fabric layer, and the microporous nanofiber membranes on both sides of the leather base fabric are two polyurethane grain layers.

2. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: The step 1 specifically includes: The polyol, diisocyanate, chain extender, catalyst and functional filler are mixed and uniformly mixed, and then the mixture is extruded through a twin-screw extruder, granulated and dried to obtain polyurethane; The weight ratio of the polyol, diisocyanate, chain extender, catalyst and functional filler is (90-100):(8-16):(6-10):(0.05-0.1):(2-4); The reaction temperature is 170-190°C.

3. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 2, characterized in that: The polyols include polyester polyols, perfluoropolyether diols and hydroxyl-terminated polydimethylsiloxanes; The mass ratio of polyester polyol, perfluoropolyether diol and hydroxyl-terminated polydimethylsiloxane is (80-100):(15-25):(20-30).

4. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: The diisocyanate includes isophorone diisocyanate; The chain extender includes dodecyl bis(hydroxyethyl)methylammonium chloride; The catalyst includes dibutyltin dilaurate.

5. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: The functional filler includes surface-modified hydrophobic silica.

6. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 5, characterized in that: The surface-modified hydrophobic silica is prepared by the following steps: The hydrophobic silica is added to an ethanol aqueous solution, the pH value is adjusted to 4-5, and after ultrasonic dispersion, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane is added to react. After the reaction is completed, the reaction is filtered, washed, and dried to obtain surface-modified hydrophobic silica.

7. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 6, characterized in that: The mass ratio of hydrophobic silica, ethanol aqueous solution, and N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane is 10:(250-350):(2-4), and the reaction conditions are 65-75° C. for 8-12 hours.

8. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: In the step 2, the mass ratio of polyurethane to organic solvent in the spinning solution is 1:(4.5-5.5).

9. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: In the step 3, the leather base fabric includes needle-punched microfiber non-woven fabric.

10. The biomimetic breathable composite material based on microporous nanofiber membrane according to claim 1, characterized in that: In the step 3, the electrospinning process parameters include: the spinning environment humidity is 50±2% RH, the spinning solution extrusion rate is 0.5-1 mL / h, the positive voltage is 25-30 kV, the negative voltage is 5 kV, and the receiving distance is 10-20 cm.

Images