阅读说明：本技术 一种粘性水凝胶及其制备方法和应用 (Adhesive hydrogel and preparation method and application thereof ) 是由 封伟 张志兴 唐林 张飞 于 2018-07-31 设计创作，主要内容包括：本发明公开一种粘性水凝胶及其制备方法和应用,首先将丙烯酰氧乙基三甲基氯化铵分散于去离子水中；其次将引发剂,催化剂加入到前一步所得溶液中,冰浴搅拌溶解后形成反应体系：再将该反应体系静置于25-70℃下反应,得到聚丙烯酰氧乙基三甲基氯化铵；最后将得到的聚丙烯酰氧乙基三甲基氯化铵加入到聚丙烯酸水溶液中,振荡得到产物,清洗得到目标粘性水凝胶。本发明利用超分子作用力,将两种带有不同电荷属性的水溶性聚合物复合,制备具有粘性可拉伸的水凝胶,并且这种水凝胶具有离子导电特性,对温度和压力变化具有敏感性,有望作为柔性的温度和压力传感器件。(The invention discloses a viscous hydrogel and a preparation method and application thereof, firstly, acryloyloxyethyl trimethyl ammonium chloride is dispersed in deionized water; secondly, adding an initiator and a catalyst into the solution obtained in the previous step, stirring and dissolving in an ice bath to form a reaction system: standing the reaction system at 25-70 ℃ for reaction to obtain polyacryl oxyethyl trimethyl ammonium chloride; and finally, adding the obtained polyacrylic acyl oxyethyl trimethyl ammonium chloride into a polyacrylic acid aqueous solution, oscillating to obtain a product, and cleaning to obtain the target viscous hydrogel. The invention utilizes supermolecule acting force to compound two water-soluble polymers with different charge attributes to prepare the viscous and stretchable hydrogel, and the hydrogel has ion conduction property, is sensitive to temperature and pressure change and is expected to be used as a flexible temperature and pressure sensing device.)

1. An adhesive hydrogel, which is characterized by consisting of polyacrylic acid and polyacrylic acid ethyl trimethyl ammonium chloride, wherein the mass ratio of the polyacrylic acid to the polyacrylic acid ethyl trimethyl ammonium chloride is (10-20): 1, the concentration of polyacrylic acid is 0.1-0.5 g/ml water, and the polyacrylic acid oxyethyl trimethyl ammonium chloride is prepared by homopolymerization of 1-5 parts by mass of acrylic acid oxyethyl trimethyl ammonium chloride.

2. The adhesive hydrogel of claim 1, wherein the mass ratio of polyacrylic acid to poly (acryloxyethyltrimethylammonium chloride) is (12-16): 1.

3. an adhesive hydrogel according to claim 1 or 3, wherein the polyacrylic acid has a weight average molecular weight of 1 to 5 ten thousand.

4. An adhesive hydrogel according to claim 1 wherein the concentration of polyacrylic acid is 0.2 to 0.5g/ml water.

5. The adhesive hydrogel of claim 1, wherein the polyacrylamide is prepared by homopolymerizing 1 to 3 parts by mass of acryloyloxyethyltrimethyl ammonium chloride.

6. The adhesive hydrogel of claim 1, wherein the polyacrylamide gel is prepared by the following steps:

step 1, uniformly dispersing acryloyloxyethyl trimethyl ammonium chloride monomers in deionized water;

and 2, adding an initiator and a catalyst tetramethyl ethylenediamine into the solution obtained in the step 1, stirring in an ice bath to dissolve, and uniformly dispersing to form a reaction system:

and 3, standing the reaction system obtained in the step 2 at 25-70 ℃ for reaction to obtain the polyacryl oxyethyl trimethyl ammonium chloride.

7. The adhesive hydrogel of claim 6, wherein the concentration of acryloyloxyethyltrimethylammonium chloride in deionized water is from 0.2 to 1g per ml of deionized water; the initiator is ammonium persulfate, and the dosage of the initiator is 3-6 mg/g of monomer relative to the mass of the acryloyloxyethyl trimethyl ammonium chloride monomer; the dosage of the catalyst tetramethylethylenediamine is 10-15 mu L/g monomer relative to the mass of the acryloyloxyethyltrimethyl ammonium chloride monomer.

8. An adhesive hydrogel according to claim 6 wherein the reaction temperature is preferably 50 to 70 ℃ and the reaction time is 4 to 24 hours, preferably 6 to 15 hours.

9. A method for preparing an adhesive hydrogel, comprising the steps of: dissolving polyacryloyloxyethyltrimethyl ammonium chloride in deionized water to form a uniform polyacryloyloxyethyltrimethyl ammonium chloride aqueous solution, adding the polyacryloyloxyethyltrimethyl ammonium chloride aqueous solution into a polyacrylic acid aqueous solution, oscillating and stirring to obtain a gel product, taking out the product, and cleaning the surface with deionized water to obtain the target viscous hydrogel, wherein the oscillating and stirring is realized mechanically or ultrasonically.

10. Use of an adhesive hydrogel according to claim 1 in temperature-sensing and pressure-sensing materials, i.e. in the preparation of pressure-and temperature-sensitive sensors.

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to an adhesive hydrogel and a preparation method and application thereof.

Background

The hydrogel is a soft material having a three-dimensional network structure and containing a large amount of moisture, and can be obtained by a physical or chemical method. The hydrogel has the characteristics of good biocompatibility, elasticity and the like, so that the hydrogel can be applied to various fields, such as drug carriers, artificial muscles, medical dressings and sensors. The hydrogel has a special three-dimensional porous structure, which is beneficial to the conduction of electrolyte ions and the occurrence of interface action, so that hydrogel-based sensing devices have been developed. At present, most of hydrogel-based sensing devices are made by filling an ionic electrolyte in hydrogel to give ionic conductivity, and further by structural design, a force-sensitive sensor (capturing an electrical signal generated by stretching or compressing) is obtained. But temperature sensitive hydrogel-based sensors have yet to be developed. In addition, a general hydrogel-based sensor needs a double-sided tape to be fixed when contacting with an object to be tested, which may cause a decrease in the accuracy of the test because the sensor does not directly contact with the object to be tested. If the hydrogel is viscous, the hydrogel can be prevented from being fixed by using a rubber belt, and can be directly contacted with an object to be tested, so that signals can be more accurately sensed and transmitted.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an adhesive hydrogel and a preparation method and application thereof, wherein the adhesive hydrogel is prepared by compounding two water-soluble polymers with different charge attributes by utilizing supermolecular acting force, has an ion conducting property, is sensitive to temperature and pressure changes, and is expected to be used as a flexible temperature and pressure sensing device.

The technical purpose of the invention is realized by the following technical scheme:

an adhesive hydrogel is composed of polyacrylic acid and polyacrylic acid ethyl trimethyl ammonium chloride, wherein the mass ratio of the polyacrylic acid to the polyacrylic acid ethyl trimethyl ammonium chloride is (10-20): 1, the concentration of polyacrylic acid is 0.1-0.5 g/ml water.

And the mass ratio of polyacrylic acid to polyacryloyloxyethyltrimethylammonium chloride is (12-16): 1.

also, polyacrylic acid (PAA) has a weight average molecular weight of 1 to 5 ten thousand.

Furthermore, the concentration of polyacrylic acid is 0.2-0.5 g per ml of water.

Further, the polyacryloyloxyethyltrimethylammonium chloride is prepared by homopolymerizing 1 to 5 parts by mass of acryloyloxyethyltrimethylammonium chloride, preferably 1 to 3 parts by mass of acryloyloxyethyltrimethylammonium chloride, each part by mass being 1 g.

Also, a method for preparing poly (acryloyloxyethyltrimethyl ammonium chloride) (PDAC) according to the following steps:

step 1, uniformly dispersing a monomer of acryloyloxyethyl trimethyl ammonium chloride (DAC) in deionized water;

and 2, adding an initiator and a catalyst Tetramethylethylenediamine (TEMED) into the solution obtained in the step 1, stirring in an ice bath to dissolve and uniformly disperse to form a reaction system:

and 3, standing the reaction system obtained in the step 2 at 25-70 ℃ for reaction to obtain the poly (acryloyloxyethyl trimethyl ammonium chloride) (PDAC).

Wherein the concentration of the acryloyloxyethyltrimethyl ammonium chloride in the deionized water is 0.2-1 g per ml of the deionized water.

The initiator is Ammonium Persulfate (APS), and the dosage of the initiator is 3-6 mg/g of monomer relative to the mass of the acryloyloxyethyl trimethyl ammonium chloride monomer (namely, 3-6 mg of initiator is used per g of acryloyloxyethyl trimethyl ammonium chloride monomer).

The amount of tetramethylethylenediamine used as the catalyst is 10 to 15. mu.L/g of monomer relative to the mass of acryloyloxyethyltrimethylammonium chloride monomer (i.e., 10 to 15. mu.L of catalyst per g of acryloyloxyethyltrimethylammonium chloride monomer).

The reaction temperature is preferably 50 to 70 ℃ and the reaction time is 4 to 24 hours, preferably 6 to 15 hours.

After the polymerization reaction is finished, the obtained PDAC aqueous solution is dialyzed for 3-4 times (the molecular weight cut-off is selected to be 3000-5000) to remove unreacted monomers and other small molecules, and then the PDAC polymer is obtained by drying at 60 ℃.

A preparation method of adhesive hydrogel comprises the following steps: dissolving polyacryloyloxyethyltrimethyl ammonium chloride in deionized water to form a uniform polyacryloyloxyethyltrimethyl ammonium chloride aqueous solution, adding the polyacryloyloxyethyltrimethyl ammonium chloride aqueous solution into a polyacrylic acid aqueous solution, oscillating and stirring to obtain a gel product, taking out the product, and cleaning the surface with deionized water to obtain the target viscous hydrogel.

The oscillation stirring is realized by selecting a mechanical mode or ultrasonic mode.

The electrical property of the viscous hydrogel changes along with the temperature and pressure changes, and the viscous hydrogel has good flexibility and certain electrical conductivity, and can be used as temperature and pressure sensing materials, namely the application in the temperature sensing materials and the pressure sensing materials.

Compared with the prior art, the invention utilizes polyacrylic acid with electronegative functional groups as a framework, and further constructs a cross-linked structure with polyacrylic acyl oxyethyl trimethyl ammonium chloride with electropositivity through the supermolecule effect to obtain hydrogel; while utilizing the cohesive properties of low molecular weight polyacrylic acids, the resulting hydrogels exhibit adhesive properties. The hydrogel prepared by the invention can be formed into any shape, shows good flexibility and certain electrical conductivity, has electrical properties sensitive to temperature and pressure changes, and can be used as a flexible temperature and pressure sensing material.

Drawings

FIG. 1 is a photograph showing the tensile properties of the hydrogel prepared according to the present invention.

FIG. 2 is a schematic diagram of the structure of a sample resistance measuring instrument (temperature change) used in the present invention.

FIG. 3 is a graph showing the temperature-sensitive property test curve of the hydrogel prepared by the present invention.

FIG. 4 is a schematic diagram of the sample resistance measuring apparatus used in the present invention (pressure change).

FIG. 5 is a graph showing the pressure-sensitive characteristics of the hydrogel prepared according to the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following drawings by way of specific examples. Acryloxyethyltrimethylammonium chloride was obtained from Beijing Bailingwei Tech Co., Ltd, ammonium persulfate was obtained from Tianjin Kemi Euro Chemicals Co., Ltd, tetramethylethylenediamine was obtained from Shanghai Aradin Biotech Co., Ltd, and polyacrylic acid solution was obtained from Shanghai Mielin Biotech Co., Ltd. Ultrasonic oscillation is adopted to realize the water gelation of the PDAC aqueous solution and the polyacrylic acid solution.