Preparation method of cooling protective clothing based on moisture absorption gel

Abstract

The invention discloses a preparation method of cooling protective clothing based on moisture absorption gel, and belongs to the field of individual protective equipment. The preparation method of the cooling protective clothing comprises the following steps: 1) performing surface treatment on a fabric by using an oxygen plasma cleaning machine, so that oxygen-containing functional groups are uniformly formed on the surface of the fabric, and the hydrophilicity of the fabric is improved; (2) the fabric subjected to surface treatment is flatly laid on a tray sprayed with water, and the fabric is attached to the surface of the tray; (3) injecting the moisture absorption gel solution into the fabric flatly laid on a tray, so that the diluted gel solution is fully diffused into the fabric; 4, a tray is subjected to low-temperature freezing or ultraviolet light curing treatment, so that the diluted gel solution and the fabric are stably combined, and the cooling protection suit based on the moisture absorption gel is obtained.The cooling protection suit achieves efficient cooling through evaporation latent heat of water and meanwhile has the advantages of being light, comfortable and easy to maintain.

Description

Technical Field

[0001] The invention relates to the field of personal protective equipment, and in particular to a method for preparing a cooling protective clothing based on a moisture absorbing gel. Background Art

[0002] As global warming intensifies, humans are working and exposed to increasing amounts of heat. High temperatures pose a serious threat to human health and may lead to heat-related illnesses such as heat stroke and dehydration, and even death in extreme cases. Studies have shown that mortality rates can increase by 5.74% under extreme high temperature conditions. In special industries and specific positions, such as key state-owned coal mines, steel smelting, shipbuilding, and firefighting and rescue, workers often face high temperatures exceeding 30°C or even as high as 50°C. These environments not only pose a threat to the physical and mental health of workers, but also seriously affect operational efficiency and safety. In hot summer weather, outdoor workers such as sanitation workers, surveying and mapping personnel, and soldiers on guard also face severe high temperature challenges.

[0003] Traditional clothing can no longer meet the special requirements of resisting high temperatures and cooling down individuals. As a simple, fast and typical protective equipment, personal cooling protective clothing is of great significance for improving the comfort of the human microclimate zone and improving work efficiency and safety in high temperature environments. However, the existing cooling clothing technology is mainly divided into two categories: active and passive, each of which has certain limitations. Active cooling clothing relies on external energy to drive the refrigerant to circulate in the clothing to effectively take away heat. This type of cooling clothing can be divided into liquid cooling clothing and air cooling clothing, using ice water or natural air / cooled air generated by air conditioning as refrigerants. The advantage of active cooling clothing is that it can control the cooling rate and provide a longer cooling effect. However, they rely on external energy, limit the wearer's range of movement and increase dependence on power. In addition, due to the built-in refrigeration components, this type of cooling clothing is often bulky, which may limit the wearer's freedom of movement, and long-term wearing may cause physical discomfort. The maintenance cost is also high, and parts such as refrigerants, compressors and pumps need to be checked and replaced regularly. Passive cooling clothing has a place in personal protective equipment for its simplicity, cost-effectiveness and portability. They do not require external energy or complex mechanical parts, are easy to maintain, are generally low cost, and are suitable for cost-effective large-scale deployment. Passive cooling clothing mainly uses phase change materials (PCM) to achieve cooling. PCM can absorb or release a large amount of latent heat during the phase change process. However, passive cooling clothing is usually unable to achieve the cooling level of active systems due to the limited use of phase change materials and the low phase change enthalpy. In addition, how to prevent the material from leaking during the phase change process and how to effectively integrate phase change materials with fabrics are current challenges.

[0004] The existing cooling clothing technology has a contradiction between temperature regulation performance and wearing comfort, and it is difficult to achieve both. Therefore, developing a new type of cooling protective clothing that provides better cooling effect and wearing experience has important practical application value and market prospects. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a cooling protective clothing based on a hygroscopic gel. The cooling protective clothing utilizes the high latent heat of evaporation of water to achieve efficient cooling, and at the same time has the characteristics of being light, comfortable and easy to maintain, and is particularly suitable for high-temperature working environments.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A method for preparing a cooling protective clothing based on a moisture-absorbing gel comprises the following steps: 1) Use an oxygen plasma cleaning machine to treat the surface of the fabric so that oxygen-containing functional groups are evenly formed on the surface of the fabric, thereby improving its hydrophilicity; 2) Spread the treated fabric on a tray sprayed with water so that the fabric fits the surface of the tray; 3) injecting the hygroscopic gel solution into the fabric laid on the tray so that the diluted gel solution is fully diffused into the fabric; 4) The tray is subjected to low-temperature freezing or UV curing treatment to allow the diluted gel solution to be stably combined with the fabric to obtain a cooling protective clothing based on the hygroscopic gel.

[0007] Furthermore, the hygroscopic gel solution in step 3) is prepared from a polymer matrix such as polyvinyl alcohol, polyacrylamide or cellulose and a water absorbent, and the water absorbent is one or two of a highly hygroscopic inorganic salt and an organic hygroscopic agent. Among them, the highly hygroscopic inorganic salt is calcium chloride, lithium bromide, lithium chloride, etc., and the organic hygroscopic agent is glycerol, etc.

[0008] Furthermore, the wet gel solution can be a polyvinyl alcohol / cellulose hydrogel solution, which is prepared by first dissolving a water absorbent with a mass fraction of 15% to 40% in water, then adding polyvinyl alcohol powder with a mass fraction of 5% to 20% and a certain amount of cellulose meal, and heating and stirring at 75 to 90° C. until the polyvinyl alcohol is completely melted to form a liquid with a certain fluidity.

[0009] Furthermore, the wet gel solution may be a polyacrylamide hydrogel solution, which is prepared by adding a certain amount of acrylamide monomer, water absorbent, initiator and crosslinking agent into water and stirring the solution at room temperature until all reagents are dissolved to form a colorless transparent liquid.

[0010] Furthermore, the amount of the hygroscopic gel solution used in step 3) is 0.3-0.5 mL / cm 2 .

[0011] Furthermore, the low-temperature freezing method described in step 4) is to place the tray in a freezer and freeze it at -60 to -40°C for 12 to 15 hours to form ice crystals and trigger phase separation, then warm the frozen fabric to room temperature to melt the ice crystals and rearrange the polymer chains to form a tight three-dimensional network structure, repeat the freezing and thawing 3 to 4 times, then remove the fabric from the tray, rinse with water to remove residual chemicals, and then dry to remove moisture to obtain a cooling protective clothing based on hygroscopic gel.

[0012] Furthermore, the UV curing method described in step 4) is to place the tray under the UV curing equipment, set the UV light intensity to 35~40W / cm², the exposure time to 10~12min, then turn the fabric over, and then perform UV treatment under the same conditions, and finally remove the cured fabric from the tray, rinse with water to remove residual chemicals, and then dry to remove moisture, to obtain a cooling protective clothing based on hygroscopic gel.

[0013] After the moisture-absorbing gel solution is combined with the fabric, a strong hydrogen bond interaction is formed between the two, providing an excellent body-fitting effect.

[0014] The working principle of the cooling suit of the present invention is that the latent heat of evaporation of water (about 2450 kJ / kg) is much higher than the phase change enthalpy of phase change material (about 200 kJ / kg). When the ambient temperature rises, the water in the hydrogel evaporates and takes away a large amount of heat, thereby cooling the human body. After the gel absorbs heat and evaporates, when the temperature drops, it can absorb water from the air again or spray water mist artificially to restore the heat dissipation capacity of the gel and realize recycling.

[0015] Compared with the prior art, the cooling clothing of the present invention has the following beneficial effects: 1. Lightweight materials: Gel-based cooling protective clothing is lightweight, much lighter than traditional phase change materials and mechanical devices such as water pipes and fans, maintaining the comfort of the fabric.

[0016] 2. Efficient heat absorption: The evaporation enthalpy of water is significantly higher than that of phase change materials, which reduces the amount of heat dissipation medium required and improves wearing comfort.

[0017] 3. Simple structure: The integrated design simplifies the production process, and the combination of gel and fabric is highly stable, which is easy to maintain and clean.

[0018] 4. Cost-effectiveness: The use of lightweight hydrogel reduces production costs and makes the price more competitive.

[0019] 5. Safety and environmental protection: All materials used are safe and environmentally friendly, non-toxic, and meet human health and environmental protection requirements.

[0020] The cooling clothing of the present invention provides an efficient, comfortable and economical cooling solution for workers in high temperature environments through its innovative design and simple preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a picture of the outdoor test scene; from left to right, it is the temperature comparison of the fabric with / without gel at the beginning, after 40 minutes, and after 2 hours, and the temperatures are 20.3 ℃ and 27.9 ℃, 24.8 ℃ and 28.2 ℃, and 28.6 ℃ and 30.9 ℃ respectively. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Example 1

[0023] Preparation of hygroscopic gel solution (polyacrylamide hydrogel solution) 0.4 g of N,N'-methylenebisacrylamide (Bis) as a cross-linking agent and 15 g of calcium chloride as a water absorbent were accurately weighed and completely dissolved in 50 ml of ultrapure water, and stirred evenly at room temperature using a magnetic stirrer until a clear solution was formed.

[0024] 8 g of acrylamide (Acr) monomer was slowly added to the above solution and stirring was continued for 2 hours to ensure the formation of a uniform aqueous solution.

[0025] During the stirring process, 0.2 g of ammonium persulfate (APS) was added as an initiator to ensure that the initiator was fully mixed with the solution to obtain a polyacrylamide hydrogel solution, i.e., a hygroscopic gel solution. Example 2

[0026] Preparation of hygroscopic gel solution (polyacrylamide / cellulose hydrogel solution) 0.5 g of N,N'-methylenebisacrylamide (Bis) as a cross-linking agent and 15 g of calcium chloride as a water absorbent were accurately weighed and completely dissolved in 50 ml of ultrapure water, and stirred evenly at room temperature using a magnetic stirrer until a clear solution was formed.

[0027] 8 g of acrylamide (Acr) monomer and 10 g of cellulose meal (solid content 1%) were slowly added to the above solution, and stirring was continued for 2 hours to ensure the formation of a uniform aqueous solution.

[0028] During the stirring process, 0.2 g of ammonium persulfate (APS) was added as an initiator to ensure that the initiator was fully mixed with the solution to obtain a polyacrylamide hydrogel solution, i.e., a hygroscopic gel solution. Example 3

[0029] Preparation of hygroscopic gel solution (polyvinyl alcohol hydrogel solution) Polyvinyl alcohol (PVA) and bacterial fiber were selected as polymer matrices, and calcium chloride (CaCl2) was used as a highly water-absorbent inorganic salt.

[0030] Dissolve 3 g of PVA and 10 g of calcium chloride in 25 ml of distilled water to form a uniform PVA-CaCl2 solution, and stir at 85 °C for 3 h using a constant temperature magnetic stirrer until the PVA is completely dissolved, i.e., a hygroscopic polyvinyl alcohol gel solution. Example 4

[0031] Preparation of hygroscopic gel solution (polyvinyl alcohol / cellulose hydrogel solution) Polyvinyl alcohol (PVA) and bacterial fiber were selected as polymer matrices, lithium chloride (LiCl) was used as highly absorbent inorganic salt, and glycerol was used as an organic hygroscopic agent.

[0032] 3 g of PVA, 0.1 g of bacterial cellulose, 10 g of LiCl, and 4 g of glycerol were dissolved in 25 ml of distilled water to form a uniform PVA-LiCl solution, which was stirred at 80 °C for 3 h using a thermostatic magnetic stirrer until the PVA was completely dissolved.

[0033] The solution was premixed for 10 minutes using an ultrasonic cell disruptor to ensure uniform mixing, thereby obtaining a polyvinyl alcohol / cellulose hydrogel solution, namely a hygroscopic gel solution. Example 5

[0034] Preparation of cooling protective clothing based on hygroscopic gel 1) Fabric pretreatment: Select suitable cotton or nylon fabrics and use an oxygen plasma cleaning machine to treat their surface. Set appropriate power and time (for example, power 100W, time 5 minutes) to ensure that oxygen-containing functional groups are evenly formed on the fabric surface, thereby improving its hydrophilicity.

[0035] 2) Fabric fixing: Take the treated fabric and lay the part of the fabric that needs to be compounded with gel on a tray that has been pre-cleaned and sprayed with distilled water. Use the viscosity of water to make the fabric fit the surface of the tray to ensure the flatness of the fabric and the uniformity of the gel distribution in the subsequent steps.

[0036] 3) Injection and curing of hygroscopic gel solution: The polyacrylamide hydrogel solution prepared in Example 1 was slowly injected into the fabric laid on the tray. A syringe or appropriate pouring tool was used to ensure that the gel solution evenly covered the fabric surface and penetrated into the fiber structure of the fabric. The amount of gel used was 0.3 mL / cm 2Then, the tray is placed under a UV curing device, and the appropriate UV light intensity and exposure time are set (for example, 36W / cm² for 10 minutes). The fabric (the part with the composite gel) is then turned over and the other side is treated with UV light again to ensure that the gel is evenly cured in the fabric to form a stable hydrogel-fabric composite material.

[0037] 4) Post-treatment: Remove the cured hydrogel-fabric composite from the tray, gently rinse it with ultrapure water to remove unreacted chemicals on the surface, and then dry it in the air or use a low-temperature drying oven (not exceeding 40°C) to remove residual moisture to obtain a cooling protective clothing based on hygroscopic gel. Example 6

[0038] Preparation of cooling protective clothing based on hygroscopic gel 1) Fabric pretreatment: Select nylon or other synthetic fabrics and use an oxygen plasma cleaning machine to treat their surface. Set appropriate power and time (for example, power 100W, time 5 minutes) to ensure that oxygen-containing functional groups are evenly formed on the fabric surface, thereby improving its hydrophilicity.

[0039] 2) Fabric fixing: Lay the cleaned nylon fabric part that needs to be compounded with gel on the prepared tray, and use a sprayer to spray distilled water to ensure that the fabric fits flat on the tray to avoid wrinkles or bubbles when injecting the gel solution.

[0040] 3) Injection and freezing of hygroscopic gel solution: The polyvinyl alcohol / cellulose hydrogel solution prepared in Example 2 was evenly injected into the flat nylon fabric, and the solution was evenly distributed on the fabric using an appropriate tool (such as a triangular coating rod). The amount of gel used was 0.5 mL / cm 2 After that, the tray was placed in a freezer and frozen at -50°C for 12 hours to form ice crystals and trigger phase separation; the frozen fabric was then warmed to room temperature to melt the ice crystals and rearrange the polymer chains to form a compact three-dimensional network structure.

[0041] To enhance the porosity and mechanical strength of the hydrogel, freezing and thawing were cycled three times to obtain the hydrogel-nylon fabric composite.

[0042] 4) Post-treatment: The hydrogel-nylon fabric composite material after completing the freeze-thaw cycle is removed from the tray, rinsed with ultrapure water to remove residual chemicals, and then dried in a low-temperature drying oven to remove residual moisture to obtain a hygroscopic gel-based cooling protective clothing. Example 7

[0043] Outdoor cooling effect test of cooling protective clothing based on moisture-absorbing gel Moisture-wicking gel-based cooling protective clothing and control clothing were prepared, and the material, size and initial temperature of the two groups of clothing were consistent.

[0044] 1) On a sunny day, place the two pieces of fabric in direct sunlight and record the initial temperature.

[0045] 2) Measure and record the fabric surface temperature at regular intervals, monitor continuously for three hours, and compare and analyze the cooling effect.

[0046] 3) After part of the water in the gel evaporates, spray water on the gel and observe the recovery of the cooling capacity.

[0047] The test results show that the fabric with the hygroscopic gel solution exhibits a significant cooling effect under direct sunlight, about 5°C lower than the fabric without gel, and the cooling effect remains stable during the three-hour test. In addition, after part of the water in the gel evaporates, the water in the gel can be quickly replenished by spraying water to restore its cooling ability.

[0048] The above embodiments demonstrate the preparation method and application scenarios of the cooling clothing of the present invention. The application test results show that the cooling clothing of the present invention can effectively provide a cooling effect for the human body and improve the comfort of the wearer.

[0049] The above embodiments are merely examples, and the protection scope of the present invention is not limited by the specific embodiments. Various changes and improvements can be made based on the principles of the present invention.

Claims

1. A method for preparing cooling protective clothing based on hygroscopic gel, characterized in that: The following steps are involved: 1) Use an oxygen plasma cleaning machine to treat the surface of the fabric so that oxygen-containing functional groups are evenly formed on the surface of the fabric, thereby improving its hydrophilicity; 2) Lay the surface-treated fabric flat on a tray sprayed with water to make the fabric fit the surface of the tray; 3) injecting the hygroscopic gel solution into the fabric laid on the tray so that the diluted gel solution is fully diffused into the fabric; 4) The tray is subjected to low-temperature freezing or UV curing treatment to allow the diluted gel solution to be stably combined with the fabric to obtain a cooling protective clothing based on the hygroscopic gel.

2. The method for preparing a cooling protective clothing based on a hygroscopic gel according to claim 1, characterized in that: Step 3) The hygroscopic gel solution is prepared from a polymer matrix and a water absorbent, wherein the water absorbent is one or both of a highly hygroscopic inorganic salt and an organic hygroscopic agent.

3. The method for preparing a cooling protective clothing based on a hygroscopic gel according to claim 2, characterized in that: The polymer matrix is ​​one or more of polyvinyl alcohol, polyacrylamide and cellulose, the water-absorbing inorganic salt is calcium chloride, lithium bromide or lithium chloride, and the organic moisture absorbent is glycerol.

4. The method for preparing a cooling protective clothing based on a hygroscopic gel according to claim 2, characterized in that: The amount of the hygroscopic gel solution used in step 3) is 0.3-0.5 mL / cm 2 .

5. The method for preparing a cooling protective clothing based on a hygroscopic gel according to claim 1, characterized in that: The low-temperature freezing method described in step 4) is to place the tray in a freezer and freeze it at -60 to -40°C for 12 to 15 hours to form ice crystals and trigger phase separation, then warm the frozen fabric to room temperature to melt the ice crystals and rearrange the polymer chains to form a tight three-dimensional network structure, repeat the freezing and thawing 3 to 4 times, then remove the fabric from the tray, rinse with water to remove residual chemicals, and then dry to remove moisture to obtain a cooling protective clothing based on hygroscopic gel.

6. The method for preparing a cooling protective clothing based on a moisture-absorbing gel according to claim 1, characterized in that: The UV curing method described in step 4) is to place the tray under the UV curing equipment, set the UV light intensity to 35~40W / cm², and the exposure time to 10~12min, then turn the fabric over, and then perform UV treatment under the same conditions, and finally remove the cured fabric from the tray, rinse with water to remove residual chemicals, and then dry to remove moisture, to obtain a cooling protective clothing based on hygroscopic gel.

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