阅读说明：本技术 一种高拉伸性自修复水凝胶及其制备方法 (High-stretchability self-repairing hydrogel and preparation method thereof ) 是由 吴旭 陈睿 徐秀彬 于丹凤 彭思玉 毛桃嫣 李泽莹 于 2019-08-29 设计创作，主要内容包括：本发明公开了一种具有高拉伸性、室温下快速自修复性能的水凝胶,所述水凝胶由以下重量份的原料在水中通过自由基聚合而成：单体丙烯酰胺4.5～5份,甲基丙烯酸二甲氨基乙酯1～1.5份,水性交联剂0.01～0.03份,引发剂0.001～0.01份；其中水性交联剂为水溶性六亚甲基二异氰酸酯三聚体。该高拉伸性自修复水凝胶克服了现有技术中自修复水凝胶强度低、环境响应性差、耐温性能差的技术不足,其具备15倍以上的高拉伸倍数,自修复率也可以高达90％,制备过程简便,水凝胶成型速度快,透光度好。这种高拉伸性自修复水凝胶在医疗领域和组织工程方面都有着广阔的应用前景。(The invention discloses a hydrogel with high stretchability and rapid self-repairing performance at room temperature, which is prepared by polymerizing the following raw materials in parts by weight in water through free radicals: 4.5-5 parts of monomer acrylamide, 1-1.5 parts of dimethylaminoethyl methacrylate, 0.01-0.03 part of water-based cross-linking agent and 0.001-0.01 part of initiator; wherein the water-based crosslinking agent is water-soluble hexamethylene diisocyanate trimer. The high-stretchability self-repairing hydrogel overcomes the technical defects of low strength, poor environmental responsiveness and poor temperature resistance of the self-repairing hydrogel in the prior art, has a high tensile multiple of more than 15 times, has a self-repairing rate of up to 90 percent, is simple and convenient in preparation process, and has high hydrogel forming speed and good transmittance. The high-stretchability self-repairing hydrogel has wide application prospects in the medical field and the tissue engineering aspect.)

1. The high-stretchability self-repairing hydrogel is characterized by being prepared by carrying out free radical polymerization on the following raw materials in parts by weight in water: 4.5-5 parts of monomer acrylamide, 1-1.5 parts of dimethylaminoethyl methacrylate, 0.01-0.03 part of water-based cross-linking agent and 0.001-0.01 part of initiator;

the water-based crosslinking agent is water-soluble hexamethylene diisocyanate trimer.

2. The hydrogel according to claim 1, which is prepared by radical polymerization of the following raw materials in water in parts by weight: 5 parts of monomer acrylamide, 1 part of dimethylaminoethyl methacrylate, 0.01 part of waterborne cross-linking agent water-soluble hexamethylene diisocyanate trimer and 0.005 part of initiator.

3. The hydrogel according to claim 1 or 2, wherein the water-soluble hexamethylene diisocyanate trimer is produced by reacting a monohydroxy polyether with a hexamethylene diisocyanate trimer.

4. The method of claim 3, wherein the mass ratio of the monohydroxy polyether to the water-soluble hexamethylene diisocyanate is 6: 5.04.

5. The method of claim 3, wherein the reaction conditions of the monohydroxy polyether and the hexamethylene diisocyanate trimer are as follows: reacting for 6-24 h at 50-100 ℃.

6. The hydrogel according to claim 5, wherein the water-soluble hexamethylene diisocyanate trimer is prepared by: adding monohydroxy polyether into a reaction vessel, heating to 100 ℃, removing water in vacuum at 100 ℃ for 2h, adding hexamethylene diisocyanate trimer when the temperature is reduced to 75 ℃, and continuously reacting at 50-100 ℃ for 6-24 h to obtain the water-soluble hexamethylene diisocyanate trimer.

7. A process for the preparation of a hydrogel according to any one of claims 1 to 6, comprising the steps of:

S1, sequentially adding an initiator ammonium persulfate, deionized water, monomer acrylamide, dimethylaminoethyl methacrylate and a water-soluble cross-linking agent water-soluble hexamethylene diisocyanate trimer into a reaction container according to a proportion, and uniformly mixing;

S2, ultrasonically treating the mixture obtained in the step S1 for 30-120S;

S3, standing the mixture obtained in the step S2 at 80-90 ℃ for reaction for 1-35 min to form hydrogel, cooling to 15-30 ℃, and taking out.

8. the method according to claim 7, wherein the mixture is allowed to stand at 90 ℃ for 5min in step S3.

9. use of the hydrogel of any one of claims 1 to 6 for the preparation of hydrogel adhesives.

10. Use of the hydrogel of any one of claims 1 to 6 for the preparation of electronic skin, flexible wearable devices, artificial cartilage.

Technical Field

the invention belongs to the field of novel high-molecular functional materials, and particularly relates to a high-stretchability self-repairing hydrogel and a preparation method thereof.

Background

Self-healing is one of the most prominent properties of biological materials such as skin, bone and wood. The specific ability of natural materials to heal fractures often involves an energy dissipation mechanism created by the sacrifice of bonds. Although synthetic hydrogels are very similar to biological tissues, they are often very brittle and lack self-healing capabilities, which prevents their use in stress-bearing applications.

In recent years, much research has been conducted to improve the mechanical properties of hydrogels formed by radical crosslinking copolymerization. The poor mechanical properties of chemically crosslinked hydrogels result primarily from their very low resistance to crack propagation. There is a lack of an efficient energy dissipation mechanism in the gel network. In order to obtain a gel with high toughness, the overall viscoelastic dissipation must be increased by forming a polymer network, in which crosslinking occurs through reversible fracture crossings. The design of self-healing materials that are capable of recovering their original mechanical properties after fracture also requires non-covalent intermolecular interactions.

the polyacrylamide is a water-soluble polymer, contains a large amount of acylamino in the structure, is easy to form hydrogen bonds, is easy to chemically modify, and is widely applied to preparation of self-repairing hydrogel. However, the traditional polyacrylamide self-repairing hydrogel has low strength, poor environmental responsiveness and poor temperature resistance, so scientists prepare self-repairing polyacrylamide hydrogels with various special functions by chemical modification, nanoparticle compounding, group introduction and other methods, but the methods are very complicated and difficult to produce in large scale. Meanwhile, most of the existing self-repairing hydrogels need longer self-repairing time and need high temperature and other conditions to realize self-repairing.

Therefore, a high-quality hydrogel with the capability of fast self-repairing at room temperature is urgently needed, which can overcome the technical defects of low stretching multiple, complex self-repairing conditions, long self-repairing time, low transparency and the like of the traditional polyacrylamide self-repairing hydrogel.

Disclosure of Invention

the technical problem to be solved is to overcome the technical defects of low stretching multiple, complex self-repairing conditions, long self-repairing time and low transparency of the self-repairing hydrogel in the prior art, and provide the hydrogel with high stretchability, rapid self-repairing performance at room temperature and high transparency.

Another object of the present invention is to provide a method for producing the above hydrogel.

The invention also aims to solve the technical problem of providing the application of the hydrogel in preparing the hydrogel adhesive.

the invention also aims to solve the technical problem of providing application of the hydrogel in preparing electronic skin, flexible wearable equipment and artificial cartilage.

The technical scheme adopted by the invention is as follows:

the high-stretchability self-repairing hydrogel is prepared by carrying out free radical polymerization on the following raw materials in parts by weight in water: 4.5-5 parts of monomer acrylamide, 1-1.5 parts of dimethylaminoethyl methacrylate, 0.01-0.03 part of water-based cross-linking agent and 0.001-0.01 part of initiator;

The water-based crosslinking agent is water-soluble hexamethylene diisocyanate trimer.

Preferably, the hydrogel is prepared by free radical polymerization of the following raw materials in parts by weight in water: 5 parts of monomer acrylamide, 1 part of dimethylaminoethyl methacrylate, 0.01 part of waterborne cross-linking agent water-soluble hexamethylene diisocyanate trimer and 0.005 part of initiator.

preferably, the initiator is ammonium persulfate.

Further, the water-soluble hexamethylene diisocyanate trimer is prepared by reacting monohydroxy polyether with hexamethylene diisocyanate trimer.

Preferably, the mass ratio of the monohydroxy polyether to the water-soluble hexamethylene diisocyanate is 6: 5.04.

Preferably, the reaction conditions of the monohydroxy polyether and the hexamethylene diisocyanate trimer are as follows: reacting for 6-24 h at 50-100 ℃.

Further, the preparation method of the water-soluble hexamethylene diisocyanate trimer comprises the following steps: adding monohydroxy polyether into a reaction vessel, heating to 100 ℃, removing water in vacuum at 100 ℃ for 2h, adding hexamethylene diisocyanate trimer when the temperature is reduced to 75 ℃, and continuously reacting at 50-100 ℃ for 6-24 h to obtain the water-soluble hexamethylene diisocyanate trimer.

The preparation method of the hydrogel comprises the following steps:

S1, sequentially adding an initiator ammonium persulfate, deionized water, monomer acrylamide, dimethylaminoethyl methacrylate and a water-soluble cross-linking agent water-soluble hexamethylene diisocyanate trimer into a reaction container according to a proportion, and uniformly mixing;

S2, ultrasonically treating the mixture obtained in the step S1 for 30-120S;

S3, standing the mixture obtained in the step S2 at 80-90 ℃ for reaction for 1-35 min to form hydrogel, cooling to 15-30 ℃, and taking out.

Preferably, the time of the ultrasonic treatment in step S2 is 60S.

preferably, the mixture is left standing at 90 ℃ for 5min in step S3.

Provides the application of the hydrogel in preparing hydrogel adhesives.

Provides the application of the hydrogel in preparing electronic skin, flexible wearable equipment and artificial cartilage.

The invention has the beneficial effects that:

The invention adopts a simple method to prepare the hyperextension self-repairing hydrogel. Compared with the traditional hydrogel, the self-repairing hydrogel has higher stretching multiple. The hydrogel has short self-repairing time, can realize self-repairing at room temperature (25-35 ℃), has a self-repairing rate of up to 90 percent and a stretching multiple of more than 15 times, can be rapidly prepared without adding an accelerant in a system, and has extremely high forming speed. In addition, the hydrogel prepared by the method has good transmittance. The high-stretchability self-repairing hydrogel has wide application prospects in the medical field and the tissue engineering aspect. In the preparation method of the hydrogel, hydrogen bonds are mainly used as a physical crosslinking mode with a self-repairing function, a polyacrylamide structure contains a large amount of amide groups, the hydrogen bonds are easy to form, complex chemical modification is not needed, the method is simple, and the preparation speed is high.

Drawings

FIG. 1 is a graph of the tensile strength and self-healing rate of hydrogels of comparative examples 1, 2 and examples 1, 2, 3.

Figure 2 stretched picture of hydrogel prepared in example 2.

FIG. 3 Infrared spectra of hydrogels of comparative examples 1 and 2 and examples 1, 2 and 3.

FIG. 4 is a graph of light transmittance of hydrogels of comparative examples 1 and 2 and examples 1, 2, and 3.

Figure 5 transmittance of the hydrogels of examples 1, 2, 3.

FIG. 6 scanning electron micrograph of hydrogel of example 2.

Detailed Description

The invention is further illustrated by the following examples. The following examples are for illustrative purposes only and are not to be construed as limiting the invention. Unless otherwise specified, the reagent raw materials used in the following examples are raw reagent raw materials which are conventionally commercially available or commercially available. Unless otherwise stated, the systems used in the following examples are equipment conventionally used in the art.