CN117604773A

CN117604773A - A hydrochromic fabric and its preparation method and application

Info

Publication number: CN117604773A
Application number: CN202311556931.5A
Authority: CN
Inventors: 张涛; 居爱明; 赵燕
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2023-11-21
Filing date: 2023-11-21
Publication date: 2024-02-27
Anticipated expiration: 2043-11-21
Also published as: CN117604773B

Abstract

The invention discloses a wet-color-changing fabric and a preparation method and application thereof, wherein the preparation method comprises the following steps: s1, adding a reaction reagent into a pH indicator solution to react to prepare a reactive pH indicator; s2, dissolving the reactive pH indicator, the hydrophilic monomer, the cross-linking agent and the photoinitiator in a solvent to obtain a finishing liquid, padding the finishing liquid on a fabric, and obtaining the wet-color fabric through photoinitiated polymerization reaction and ion exchange reaction; the hydrophilic monomer is an ammonium salt monomer. The prepared wet-color-changing fabric has strong hygroscopicity and can change the color obviously and reversibly along with the change of the environmental humidity; because the pH indicator and the hygroscopic material are connected with the fabric through covalent bonds, the fabric has the characteristics of wear resistance, good washing resistance and the like; the fabric also has the advantages of good flexibility, good air permeability and the like. The wet-color fabric has wide application prospects in the aspects of humidity indication, pH detection, humidity management, evaporative cooling and the like.

Description

Wet electrochromic fabric and preparation method and application thereof

Technical Field

The invention relates to the technical field of wet-color-changing materials, in particular to a wet-color-changing fabric and a preparation method and application thereof.

Background

A wet-chromic material is a material that can undergo a color change upon interaction with water vapor. The color-changing silica gel used as a desiccant is a common wet-color-changing material which can be used for drying and judging the drying capacity through color change. The wet-color-changing function is combined with the textile, so that the wet-color-changing performance of the textile can be endowed, and the wet-color-changing textile with humidity management and humidity monitoring functions is obtained and is used for constructing diversified and functional textiles. Meanwhile, due to the excellent mechanical properties of the fabric, the wet-color fabric is obviously superior to the conventional wet-color material, and has good flexibility and shape diversity.

Recent studies have shown that wet-chromic materials can be prepared by humidity-induced discolouration of pH-chromic agents. Specifically, the moisture-sensitive material can release free protons after absorbing water vapor, and the free protons induce the conjugated structure of the pH indicator to change, so that the color change is macroscopically shown. In humidity-induced pH color-changing materials, a material capable of releasing free protons after absorbing water vapor is required to be used as an acid-base adjusting component, and the pH value of a system is adjusted after the material is combined with water; the pH indicator is used as a color-changing component, and the color change occurs through accepting or losing protons; in addition, in order to enhance the ability of the thermochromic material to absorb moisture from the air, it is often necessary to add a hygroscopic component. Most pH-indicating based electrochromic materials, however, use inorganic materials as the base material, which brittleness and low mechanical properties may hinder their potential applications.

The prior art successfully prepares a wet-color-changing fabric (High sensitivity-sensitive discoloration materials fabricated with pH indicator ingredients, dyes and Pigments,2021,195,109740) based on a pH indicator, wherein the fabric is prepared by using silica gel and hydrophilic silica aerogel as hygroscopic materials, cresol red or thymol blue (pH indicator) as a color-changing component and boric acid as an acid-base adjusting component through a screen printing method. The color-changing fabric has the advantages of good flexibility, good mechanical property, quick response to humidity, obvious color change, stable color transition and the like. However, considering the characteristics of screen printing, such a wet-chromic fabric has the following drawbacks: the pH indicator and boric acid may leak during use (particularly after direct contact with liquid water) and are subject to improvement in wear resistance, wash resistance, and air permeability.

Disclosure of Invention

In order to solve the technical problems, the primary object of the invention is to provide a preparation method of a wet-color-changing fabric, which is to prepare the wet-color-changing fabric based on humidity-induced pH indicator color change by grafting and polymerizing hydrophilic monomers and a reactive pH indicator on the surface of the fabric.

The invention further aims to provide the wet-color-changing fabric prepared by the method, which shows reversible color change from blue to yellow after the relative humidity is increased, and has the advantages of high reusability, good flexibility, strong hygroscopicity, capability of reversible color change along with humidity change, good durability and air permeability and the like.

A third object of the present invention is to provide the use of the above described thermochromic fabric for humidity indication, pH detection, humidity management and evaporative cooling.

The above object of the present invention is achieved by the following technical scheme:

the first aspect of the invention provides a method for preparing a wet-chromic fabric, comprising the steps of:

s1, adding a reaction reagent into a pH indicator solution to react to prepare a reactive pH indicator; the reaction reagent is acyl halide, anhydride or isocyanate compound;

s2, dissolving the reactive pH indicator, the hydrophilic monomer, the cross-linking agent and the photoinitiator in a solvent to obtain a finishing liquid, padding the finishing liquid on a fabric, and obtaining the wet-color fabric through photoinitiated polymerization reaction and ion exchange reaction; the hydrophilic monomer is an ammonium salt monomer.

According to the invention, the ultraviolet light and the photoinitiator are used for initiating free radical graft polymerization, so that the reactive pH indicator, the hydrophilic monomer, the cross-linking agent and the lateral group of the fabric fiber are subjected to graft polymerization to form covalent connection, thus the pH indicator and the moisture-absorbing material cannot be stripped or leaked in use, and the fabric has higher wear resistance and washing resistance; the flexibility and the shape diversity of the fabric are well maintained, and the fabric still has good air permeability; the hygroscopic material can effectively enhance the capability of the fabric for absorbing water vapor from the air, the ion exchange replaces chloride ions on hydrophilic monomer quaternary ammonium salt with acetate ions, so that the hygroscopicity is enhanced, and meanwhile, the change of the quaternary ammonium salt groups can change the color change behavior of the fabric; the polymer network formed by polymerization imparts reversible wet-chromic capability to the fabric; the fabric has similar color change behavior after multiple times of washing and has good washing fastness.

Specifically, in the step S1, when the reactant is an acyl halide or anhydride compound, an acid binding agent is added to absorb acid generated by the reaction to promote the reaction to proceed smoothly, and the acid binding agent is triethylamine, pyridine or N, N-diisopropylethylamine.

The reaction reagent is preferably an isocyanate-based compound in view of convenience of purification.

Further, in step S1, the reactant is an acryl halide, a methacryl halide, an acrylic anhydride, a methacrylic anhydride, an isocyanate acrylate or an isocyanate methacrylate.

Specifically, in step S1, the pH indicator solution includes a pH indicator and a solvent, wherein the solvent is one or more of dichloromethane, chloroform, dimethyl sulfoxide, N-dimethylformamide, N-dimethylacetamide, and tetrahydrofuran.

Further, in step S1, the pH indicator is one or more of thymol blue, bromophenol blue, bromocresol green, chlorophenol red, bromocresol purple, phenol red, cresol red, bromothymol blue, phenolphthalein, 1-naphtholphthalein, and thymolphthalein.

Preferably, in step S1, the molar ratio of the reaction reagent to the pH indicator is (1-2): 1.

Preferably, in step S1, the reaction time is greater than 5 hours.

Further, in step S2, the hydrophilic monomer is one or more of allyl trimethyl ammonium chloride, acryloxyethyl trimethyl ammonium chloride, methacryloxyethyl trimethyl ammonium chloride, acryloxyethyl dimethyl benzyl ammonium chloride, methacryloxyethyl dimethyl benzyl ammonium chloride, dimethyl diallyl ammonium chloride, (3-acrylamidopropyl) trimethyl ammonium chloride, allyl trimethyl ammonium bromide, and bromomethyl dimethyl ammonium bromide.

Further, in step S2, the crosslinking agent is one or more of N, N-methylenebisacrylamide, polyethylene glycol diacrylate and polyethylene glycol dimethacrylate.

Further, in step S2, the photoinitiator is one or more of a photoinitiator 1173, a photoinitiator 2959, a photoinitiator 127, a photoinitiator 184, a photoinitiator 369, a photoinitiator 379, a photoinitiator 907, a photoinitiator 1110, a photoinitiator 1101, a photoinitiator 1220, a photoinitiator 1046, a photoinitiator 1156, a photoinitiator 651, a photoinitiator 754, a photoinitiator 819, a photoinitiator EHA, a photoinitiator MBP, a photoinitiator MBF, a photoinitiator OMBB, a photoinitiator PBZ, a photoinitiator TPO-L, a photoinitiator BDK, a photoinitiator BP, a photoinitiator 1000, a photoinitiator 4265, a photoinitiator 500, and a photoinitiator DETX.

Further, in step S2, the solvent is one or more of water, N-dimethylformamide, N-dimethylacetamide, methanol, ethanol and acetone.

Further, in step S2, the fabric is cotton, hemp, silk, wool, terylene, chinlon, spandex, vinylon, acrylon, polypropylene, polyvinyl chloride, aramid, regenerated cellulose, regenerated protein fiber fabric or a blended fabric thereof.

Further, in the step S2, the mass ratio of the reactive pH indicator to the hydrophilic monomer to the cross-linking agent to the photoinitiator to the solvent is (0.1-0.5): 4-8): 0.4:0.1 (1.4-5.4).

Further, in step S2, the ion-exchanged aqueous solution is an aqueous solution composed of one or more of acetate, oxalate, sulfate, nitrate, carbonate and bicarbonate.

Preferably, in step S2, the impregnation time per ion exchange is greater than 6 hours and the number of impregnations is greater than 2.

According to a second aspect of the present invention, there is provided a wet-chromic fabric prepared by the method according to the first aspect, the wet-chromic fabric having strong hygroscopicity and breathability; the color of the fabric can be obviously and reversibly changed along with the change of the ambient humidity; the fabric has a pH indicating function, and the color of the fabric can be obviously changed along with the pH; the fabric has the function of evaporating and cooling; the fabric has excellent wear resistance and washing resistance, does not generate obvious color drop after friction and washing, and has the advantages of high reusability, good flexibility, strong hygroscopicity, capability of generating reversible color conversion along with humidity change, good durability and air permeability and the like.

In a third aspect, the present invention provides the use of the thermochromic fabric according to the second aspect for humidity indication, pH detection, humidity management and evaporative cooling.

The invention has the beneficial effects that:

1. according to the invention, the ultraviolet light and the photoinitiator are used for initiating free radical graft polymerization, so that the reactive pH indicator, the hydrophilic monomer, the cross-linking agent and the lateral group of the fabric fiber are subjected to graft polymerization to form covalent connection, and therefore, the pH indicator and the moisture-absorbing material cannot be stripped and leaked in use; the hygroscopic material can effectively enhance the capability of the fabric for absorbing water vapor from the air, the ion exchange replaces chloride ions on hydrophilic monomer quaternary ammonium salt with acetate ions, so that the hygroscopicity is enhanced, and meanwhile, the change of the quaternary ammonium salt groups can change the color change behavior of the fabric; the polymeric network formed by the polymerization imparts reversible wet-chromic capability to the fabric.

2. The wet-color-changing fabric provided by the invention has stronger hygroscopicity and air permeability; the color of the fabric can be obviously and reversibly changed along with the change of the ambient humidity; the fabric has a pH indicating function, and the color of the fabric can be obviously changed along with the pH; the fabric has the function of evaporating and cooling; the fabric has excellent wear resistance and washing resistance, does not generate obvious color drop after friction and washing, and has the advantages of high reusability, good flexibility, strong hygroscopicity, capability of generating reversible color conversion along with humidity change, good durability and air permeability and the like.

Drawings

FIG. 1 is a physical view of the wet color textile prepared in example 1.

Fig. 2 is an optical micrograph of a cotton fabric and a wet-chromic fabric prepared in example 1.

FIG. 3 is a scanning electron microscope image of cotton fabric and the wet-chromic fabrics prepared in examples 1-3.

Fig. 4 is a graph showing the comparison of the moisture absorption rates of cotton fabrics, the wet-chromic fabrics prepared in examples 1 to 3, and the wet-chromic fabrics prepared in comparative example 2 at different humidities.

Fig. 5 is a graph of reflectance of the wet-chromic fabric prepared in example 1 at various humidities.

Fig. 6 is a graph of data for values of a and b for the wet-chromic fabrics prepared in example 1 at different humidities.

FIG. 7 is a graph of K/S value data for the wet-chromic fabrics prepared in examples 1, 4 and 5 in the dry state.

Fig. 8 is a graph of air permeability data for cotton fabrics and the wet-chromic fabrics prepared in examples 1-3 in the dry state.

Fig. 9 is a graph showing the temperature change of cotton fabrics and the wet-chromic fabrics prepared in example 3 when heated at 50 ℃.

Detailed Description

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to be limiting, so that those skilled in the art will better understand the invention and practice it.

The experimental methods used in the following examples are conventional methods unless otherwise specified, and materials, reagents, etc. used, unless otherwise specified, are commercially available.

Example 1

A method for preparing a wet-chromic fabric, comprising the steps of:

s1, dissolving 0.624g of bromothymol blue in 20mL of tetrahydrofuran solution, and then adding 0.212g of isocyanate ethyl acrylate for reaction to prepare a reactive pH indicator;

s2, dissolving 0.1g of a reactive pH indicator in 3.4g of N, N-dimethylacetamide, adding 80wt.% of aqueous solution of 6.0g of acryloyloxyethyl trimethyl ammonium chloride, 0.4g of polyethylene glycol diacrylate and 0.1g of photoinitiator 1173, stirring uniformly to obtain a finishing liquid, padding 1g of cotton fabric in 10g of the finishing liquid, taking out the cotton fabric, and using ultraviolet light (365 nm,100W/m ² ) The fabric was subjected to ion exchange by immersing it in 5wt.% sodium acetate solution for 10 minutes, 3 times each for 6 hours, and washed and dried to obtain a wet-chromic fabric (sample 1).

Example 2

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the amount of the aqueous solution of acryloyloxyethyl trimethylammonium chloride was 4.0g and the amount of N, N-dimethylacetamide was 5.4g, to obtain a wet photochromic fabric (sample 2).

Example 3

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the amount of the aqueous acryloyloxyethyl trimethylammonium chloride solution was 8.0g and the amount of N, N-dimethylacetamide was 1.4g, to obtain a wet electrochromic fabric (sample 3).

Example 4

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the amount of the reactive pH indicator was 0.3g and the amount of N, N-dimethylacetamide was 3.2g, to obtain a wet-chromic fabric (sample 4).

Example 5

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the amount of the reactive pH indicator was 0.5g and the amount of N, N-dimethylacetamide was 3.0g, to obtain a wet-chromic fabric (sample 5).

Example 6

A method for preparing a wet-chromic fabric, which is the same as that of example 1, except that step S1 is modified as follows: 0.624g bromothymol blue was dissolved in 20mL tetrahydrofuran solution, and then 0.141g isocyanate ethyl acrylate was added to react to prepare a reactive pH indicator.

Example 7

A method for preparing a wet-chromic fabric, which is the same as that of example 1, except that step S1 is modified as follows: a reactive pH indicator was prepared by dissolving 0.624g bromothymol blue in 20mL tetrahydrofuran solution, and then adding 0.156g methacryloyl chloride and 0.2mL triethylamine to react.

Example 8

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the hydrophilic monomer is replaced by allyl trimethyl ammonium chloride.

Example 9

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the hydrophilic monomer is replaced by dimethyldiallylammonium chloride.

Example 10

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the crosslinking agent is replaced by N, N-methylene bisacrylamide.

Example 11

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the initiator is replaced with photoinitiator 2959.

Example 12

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the solvent was replaced with ethanol.

Example 13

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the fabric used was a polyester fabric.

Example 14

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the fabric used was a nylon fabric.

The resulting wet-color-changing polyester fabrics prepared in examples 6 to 14 had similar color-changing behavior to example 1.

Comparative example 1

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the reactive pH indicator was replaced with a commercial pH indicator without any treatment.

The wet-color-changing fabric prepared in comparative example 1 has similar color-changing behavior to that of example 1, but the pH indicator is easy to fall off after washing and has poor fastness.

Comparative example 2

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: no ion exchange operation was performed to give a wet-chromic fabric (sample 6).

Comparative example 3

A method for preparing a wet-chromic fabric, identical to the method of example 1, with the difference that: the hydrophilic monomer is replaced with acrylamide.

The wet electrochromic fabric prepared in comparative example 3 did not have the ability to wet electrochromic.

Fig. 1 is a physical diagram of the wet-color fabric prepared in example 1, and it can be seen from the figure that the wet-color fabric provided by the invention has good flexibility and can be bent and folded.

Fig. 2 is an optical micrograph of a cotton fabric and a wet-chromic fabric prepared in example 1, from which it can be seen that the wet-chromic fabric retains the original texture of the fabric because polymerization occurs on the fibers without blocking the gaps between yarns.

Fig. 3 is a scanning electron microscope image of cotton fabric and the wet-chromic fabric prepared in examples 1-3, from which it can be seen that the wet-chromic fabric surface has a rough layer compared to the original cotton fabric, and the rough layer becomes more and more pronounced from sample 2 to sample 1 and then to sample 3, indicating that an increase in the amount of hydrophilic monomer will result in more polymer formation on the fabric surface.

Fig. 4 is a graph showing the comparison of the moisture absorption rates of cotton fabrics, the wet-color fabrics prepared in examples 1 to 3, and the wet-color fabrics prepared in comparative example 2 at different humidity, and it can be seen from the graph that the moisture absorption of sample 2 is lower than that of sample 1, and that the moisture absorption of sample 3 is higher than that of sample 1, because the amount of the moisture-absorbing polymer on the fabrics gradually increases from sample 2 to sample 1 and then to sample 3, and the moisture-absorbing polymer can effectively enhance the ability of the fabrics to absorb water vapor from the air, and more moisture-absorbing polymer can make the fabrics have stronger moisture absorption. Compared with sample 1 and sample 6, sample 6 has reduced hygroscopicity, greatly prolonged color change time, and insignificant color change, because the ammonium acetate group after ion exchange has stronger hygroscopicity than the ammonium chloride group, and the change of the group also affects the color change performance of the fabric.

Fig. 5 is a graph of reflectance of the wet-color fabric prepared in example 1 at different humidities, and fig. 6 is a graph of data of a and b values of the wet-color fabric prepared in example 1 at different humidities, where a is a red-green axis and positive and negative values respectively indicate red and green in Lab chromaticity space; the values of b represent Huang Lanzhou, positive and negative values represent yellow and blue, respectively, and figures 5 and 6 demonstrate that the polymeric networks polymerized according to the present invention impart reversible wet-chromic capability to fabrics.

FIG. 7 is a graph of K/S values representing the degree of surface shading, and the greater the value, the darker the color, for the wet-chromic fabrics prepared in examples 1, 4 and 5, as can be seen from the graph, samples 4 and 5 have a darker color than sample 1, with an increase in the amount of reactive pH indicator that would darken the fabric.

Fig. 8 is a graph showing air permeability data of cotton fabrics and the wet electrochromic fabrics prepared in examples 1 to 3 in a dry state, and it can be seen from the graph that the wet electrochromic fabrics have air permeability similar to that of the cotton fabrics, so that the wet electrochromic fabrics prepared in the invention still have good air permeability.

Application example 1 humidity indication

The color of the wet-chromic fabrics prepared in example 1 was measured at different humidities and the test results are shown in fig. 6 and 7. Fig. 6 shows the reflectance curves for sample 1 at 0%, 33%, 59%, 85% and 98% RH. As the humidity increased, the reflection peaks of sample 1 appeared at 485nm, 500nm, 525nm, 540nm and 565nm, respectively. In fig. 7, the values of a, b, and a for sample 4 at 0%, 33%, 59%, 85%, and 98% RH are-15.0, -13.4, -12.0, -7.4, 3.4, and-8.1, 6.7, 16.6, 22.7, and 35.4, respectively. These results all indicate that as the relative humidity increases, the color transition from blue to yellow occurs in the wet-chromic fabric.

The wet-color-changing fabric can change in obvious reversible color along with the change of the ambient humidity, namely, the wet-color-changing fabric can change from blue to yellow along with the increase of the relative humidity, and can change from yellow to blue along with the decrease of the relative humidity, so that the wet-color-changing fabric can be used for humidity indication.

Application example 2pH detection

The wet-color-changing fabric has a pH indication function, and is yellow in an acidic solution with the pH less than or equal to 6, yellow-green in a neutral solution with the pH=7, green in an alkaline solution with the pH=8 and blue in an alkaline solution with the pH more than or equal to 9, so that the acidic, neutral and alkaline solutions with the corresponding pH values are distinguished. In addition, can also be used for monitoring leakage of acid-base gas.

Application example 3 humidity management

The wet-color fabric of the invention has strong hygroscopicity, and as shown in fig. 5, the wet-color fabric prepared in example 1 has a moisture absorption rate of up to 45% at 98% RH, and can be used for humidity management.

Application example 4 evaporative cooling

After the wet-color-changing fabric is fully absorbed in an RH environment of 85%, the wet-color-changing fabric is placed on a heating plate at 50 ℃, so that the cooling effect of about 1-2 ℃ compared with that of pure cotton fabric can be realized, as shown in fig. 9, fig. 9 is a temperature change chart of the cotton fabric and the wet-color-changing fabric prepared in the embodiment 3 when the wet-color-changing fabric is heated at 50 ℃, and the wet-color-changing fabric can be used for evaporative cooling.

The above-described embodiments are merely preferred embodiments for fully explaining the present invention, and the scope of the present invention is not limited thereto. Equivalent substitutions and modifications will occur to those skilled in the art based on the present invention, and are intended to be within the scope of the present invention. The protection scope of the invention is subject to the claims.

Claims

1. A method for preparing hydrochromic fabrics, which is characterized by comprising the following steps:

S1. Add the reaction reagent to the pH indicator solution for reaction to prepare a reactive pH indicator; the reaction reagent is an acid halide, anhydride or an isocyanate compound;

S2. Dissolve the above reactive pH indicator, hydrophilic monomer, cross-linking agent, and photoinitiator in a solvent to obtain a finishing liquid, pad the finishing liquid on the fabric, and obtain the desired result through photoinitiated polymerization reaction and ion exchange reaction. The hydrochromic fabric; the hydrophilic monomer is an ammonium salt monomer.

2. The preparation method according to claim 1, characterized in that, in step S1, the reaction reagent is acrylic acid halide, methacrylic acid halide, acrylic anhydride, methacrylic anhydride, isocyanate acrylate or isocyanate methyl. Acrylate.

3. The preparation method according to claim 1, characterized in that, in step S1, the pH indicator is thymol blue, bromophenol blue, bromocresol green, chlorophenol red, bromocresol purple, phenol One or more of red, cresol red, bromothymol blue, phenolphthalein, 1-naphtholphthalein and thymolphthalein.

4. The preparation method according to claim 1, characterized in that, in step S2, the hydrophilic monomer is allyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, Methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyldimethylbenzylammonium chloride, methacryloyloxyethyldimethylbenzylammonium chloride, dimethyldiallyl One or more of ammonium chloride, (3-acrylamidopropyl)trimethylammonium chloride, allyltrimethylammonium bromide and bromomethenyldimethylammonium bromide.

5. The preparation method according to claim 1, characterized in that, in step S2, the cross-linking agent is N,N-methylene bisacrylamide, polyethylene glycol diacrylate and polyethylene glycol diacrylamide. One or more methacrylates.

6. The preparation method according to claim 1, characterized in that in step S2, the photoinitiator is photoinitiator 1173, photoinitiator 2959, photoinitiator 127, photoinitiator 184, photoinitiator 369 , photoinitiator 379, photoinitiator 907, photoinitiator 1110, photoinitiator 1101, photoinitiator 1220, photoinitiator 1046, photoinitiator 1156, photoinitiator 651, photoinitiator 754, photoinitiator 819 , photoinitiator EHA, photoinitiator MBP, photoinitiator MBF, photoinitiator OMBB, photoinitiator PBZ, photoinitiator TPO, photoinitiator TPO-L, photoinitiator BDK, photoinitiator BP, photoinitiator One or more of agent 1000, photoinitiator 4265, photoinitiator 500 and photoinitiator DETX.

7. The preparation method according to claim 1, characterized in that in step S2, the fabric is cotton, linen, silk, wool, polyester, nylon, spandex, vinylon, acrylic, polypropylene, chlorine fiber, aramid, Regenerated cellulose, regenerated protein fiber fabrics or their blended fabrics.

8. The preparation method according to claim 1, characterized in that in step S2, the mass ratio of the reactive pH indicator, hydrophilic monomer, cross-linking agent, photoinitiator and solvent is (0.1~ 0.5):(4～8):0.4:0.1:(1.4～5.4).

9. The preparation method according to claim 1, characterized in that, in step S2, the aqueous solution of the ion exchange is acetate, oxalate, sulfate, nitrate, carbonate and bicarbonate. Aqueous solution of one or more compositions.

10. A hydrochromic fabric prepared by the method according to any one of claims 1 to 9.