阅读说明：本技术 一种双键化丁香酚交联的仿贻贝高粘附水凝胶及其制备方法 (Double-bonded eugenol crosslinked mussel-like high-adhesion hydrogel and preparation method thereof ) 是由 马建中 刘晨阳 张跃宏 张雷 于 2020-07-14 设计创作，主要内容包括：本发明涉及一种基于双键化丁香酚交联的仿贻贝高粘附水凝胶的制备方法,所述水凝胶是以丙烯酰胺为主单体,过硫酸铵为引发剂,多巴胺甲基丙烯酰胺为高粘附性共聚单体,由双键化丁香酚交联得到；本发明是为了解决现有水凝胶在水下环境粘附强度低,同时使用不可再生石油基交联剂的问题。制备方法如下：(1)多巴胺甲基丙烯酰胺的制备；(2)双键化丁香酚的制备；(3)双键化丁香酚交联仿贻贝高粘附水凝胶的制备。本发明通过引入多巴胺甲基丙烯酰胺高粘附性共聚单体来提高水凝胶的水下粘附强度,并以双键化丁香酚作为生物质基交联剂来提高水凝胶的力学强度,最终得到兼具良好机械强度、水下粘附性的仿贻贝水凝胶。(The invention relates to a preparation method of a mussel-like high-adhesion hydrogel based on double-bonded eugenol crosslinking, wherein the hydrogel is obtained by crosslinking double-bonded eugenol by taking acrylamide as a main monomer, ammonium persulfate as an initiator and dopamine methacrylamide as a high-adhesion comonomer; the invention aims to solve the problems that the existing hydrogel has low adhesion strength in an underwater environment and a nonrenewable petroleum-based crosslinking agent is used. The preparation method comprises the following steps: (1) preparing dopamine methacrylamide; (2) preparing double-bonded eugenol; (3) and (3) preparing the double-bonded eugenol cross-linked mussel-like high-adhesion hydrogel. According to the invention, the underwater adhesion strength of the hydrogel is improved by introducing the dopamine methacrylamide high-adhesion comonomer, and the mechanical strength of the hydrogel is improved by using double-bonded eugenol as a biomass-based crosslinking agent, so that the mussel-like hydrogel with good mechanical strength and underwater adhesion is finally obtained.)

1. A preparation method of a double-bonded eugenol crosslinked mussel-like high-adhesion hydrogel is characterized by comprising the following steps:

and (3) carrying out free radical polymerization reaction by using acrylamide as a main monomer, dopamine methacrylamide as a comonomer and double-bonded eugenol as a cross-linking agent to obtain the mussel-like high-adhesion hydrogel.

2. The method as claimed in claim 1, wherein the mass ratio of acrylamide, dopamine methacrylamide and double bonded eugenol is (100- & 400): (10-30): (5-15).

3. The method of claim 1, wherein the radical polymerization is a solution polymerization using an acetone-water mixed solvent.

4. The method of claim 1, comprising the steps of:

mixing 10-30 parts of dopamine methacrylamide, 5-15 parts of double-bonded eugenol and 2400 parts of acetone by mass, and fully stirring to obtain a solution A;

dissolving 100-400 parts of acrylamide in 300-900 parts of water to obtain a solution B;

and uniformly mixing the solution A and the solution B, adding 3-9 parts of ammonium persulfate, uniformly dispersing, and fully reacting under the condition of free radical polymerization.

5. The method of claim 1, wherein said dopamine methacrylamide is obtained by introducing a double bond containing methacrylic anhydride into dopamine hydrochloride via an amidation reaction.

6. The method of claim 5, wherein said dopamine methacrylamide is obtained by a method comprising the steps of:

according to the mass portion, 10-30 portions of sodium tetraborate and 4-12 portions of sodium bicarbonate are dissolved in 100 portions of deionized water and 300 portions of deionized water, then the mixture is placed in a reactor at 25 ℃, and N is introduced under the condition of good air tightness₂Reacting for 30-60 min; adding 5-15 parts of dopamine hydrochloride into the reactor, slowly dropwise adding the mixed solution of methacrylic anhydride and tetrahydrofuran, controlling the pH to be more than 8.0 in the process, and continuously introducing N₂Reacting for 14-18 h; washing the generated suspension twice by using ethyl acetate, and then adjusting the pH to 1.0-3.0 by using 6mol/L hydrochloric acid aqueous solution; extracting with ethyl acetate for 3 times, drying the organic phase with anhydrous magnesium sulfate, and vacuum filtering; adding the obtained filtrate into n-hexane for settling and stirring, standing overnight at 4 ℃, and drying in vacuum to obtain the dopamine methacrylamide.

7. The method of claim 1, wherein the doubly-bonded eugenol is derived from the esterification of biomass-based eugenol with methacrylic anhydride.

8. The method of claim 7, wherein the doubly-bonded eugenol is obtained by a process comprising the steps of:

adding 20-60 parts of eugenol into a reactor according to the parts by weight, and introducing N under the condition of good air tightness₂Reacting for 2-3h to remove O₂And moisture; slowly dropping methacrylic anhydride into the reactor, gradually raising the temperature to 40-60 ℃, and continuously introducing N₂Reacting for 24 hours; transferring the product into a beaker, and adding dichloromethane with the volume 2-4 times that of the product into the beaker for dilution; adding sodium bicarbonate water solution with the volume 4 times that of the product to wash the product with water, and repeating the washing until no bubbles are generated; washing the organic layer with 1.0mol/L sodium hydroxide aqueous solution, 0.5mol/L sodium hydroxide aqueous solution and 1.0mol/L hydrochloric acid solution in sequence; adding excessive anhydrous magnesium sulfate to dry the product, filtering, distilling under reduced pressure, drying in an oven at 40-80 deg.C overnight to obtain double bondAnd (4) dissolving eugenol.

9. The method of claim 1, comprising the steps of:

dissolving 10-30 parts of dopamine methacrylamide and 5-15 parts of double-bonded eugenol in 2400 parts of acetone solution by mass, and fully stirring until the dopamine methacrylamide and the double-bonded eugenol are completely dissolved to obtain a solution A; dissolving 100-400 parts of acrylamide in 300-900 parts of neutral deionized water to obtain a solution B; and mixing the solution A and the solution B, uniformly stirring, adding 3-9 parts of ammonium persulfate, stirring for 30-60min, and fully reacting at 60-80 ℃ for 3-4h to obtain the double-bonded eugenol crosslinked mussel-imitated high-adhesion hydrogel.

10. A double-bonded eugenol crosslinked mussel-like high-adhesion hydrogel obtainable by the process according to any one of claims 1 to 9.

Technical Field

The invention belongs to the field of hydrogel and preparation thereof, and particularly relates to a preparation method of double-bonded eugenol crosslinked mussel-imitated high-adhesion hydrogel.

Background

Hydrogel is a material with excellent biocompatibility, has a three-dimensional cross-linked structure similar to extracellular matrix in a human body, has excellent physicochemical properties and biological properties such as certain strength, unique water absorption and retention capacity, controllable drug release, good biological adhesion and biocompatibility and the like, and is widely applied to the fields of wound dressings, drug controlled release materials, adhesives and the like. At present, the existing hydrogel adhesive has the defects of poor mechanical strength, poor adhesive property, obvious reduction of adhesive property in water environment and even loss of adhesive force, so that the application range of the hydrogel adhesive is greatly limited. Therefore, there is a strong need to improve the mechanical strength of hydrogels and to impart underwater adhesion thereto in order to expand the application fields of hydrogel adhesives.

In recent years, excessive use of petroleum-based resources has brought about serious problems of environmental pollution and resource exhaustion. Thus, the development of biomass-based crosslinking agents has received increasing attention from researchers. The eugenol as a biomass-based compound has the advantages of low cost and wide source. However, the allylic double bond contained in the eugenol is low in activity, and the phenolic hydroxyl group of the eugenol has a polymerization inhibition effect, so that the eugenol is difficult to perform self polymerization.

The adhesive protein of marine mussels has an ultra-strong underwater adhesion effect so that the marine mussels can be firmly adhered to the surfaces of various substrates. Research shows that the super-strong adhesive capacity of the mussel is related to 3, 4-Dihydroxyphenylalanine (DOPA) in adhesive protein secreted by byssus thereof, and the DOPA serving as a main functional group of the mussel adhesive protein can form interaction with different matrix materials to show very strong adhesive capacity. However, natural mussels have low content of adhesive protein and poor water solubility, and the direct extraction of adhesive protein is complicated and costly, and is difficult to apply and popularize.

Disclosure of Invention

For the problem that eugenol is difficult to self-polymerize, phenolic hydroxyl in eugenol can be converted into methacrylate groups with higher activity, so that double-bonded eugenol (ME) is introduced into a hydrogel system, and a rigid benzene ring on the structure of the double-bonded eugenol and two double bonds on the structure of the double-bonded eugenol are copolymerized with double bonds on acrylamide and dopamine methacrylamide structures respectively to endow the hydrogel with higher mechanical strength. The extraction operation of the adhesive protein of the natural mussel is complex and the cost is high, and the Dopamine Methacrylamide (DMA) with catechol groups and amino groups can be used as a precursor of the mussel adhesive protein by simulating the molecular structure of the mussel adhesive protein and is introduced into a Polyacrylamide (PAM) hydrogel system to endow the hydrogel with good underwater adhesion property. The structure of the prepared hydrogel is shown as the following formula, and the formula (1) is the structural formula (DMA-ME-PAM) of the hydrogel:

the invention provides a preparation method of double-bonded eugenol crosslinked mussel-like high-adhesion hydrogel, which aims to solve the problems of poor mechanical strength, low bonding strength and obvious reduction and even loss of adhesion in a water environment of the conventional hydrogel adhesive. According to the method, double-bonded eugenol is used as a biomass crosslinking agent, and the hydrogel with good underwater bonding performance and mechanical strength is prepared by performing free radical copolymerization reaction on acrylamide and dopamine methacrylic anhydride under a neutral condition.

The technical scheme adopted by the invention is as follows:

the invention provides a mussel-imitated high-adhesion hydrogel which is environment-friendly, good in mechanical property and has underwater adhesion, and is prepared by using double-bonded eugenol as a biomass-based cross-linking agent and dopamine methacrylamide as a high-adhesion copolymerization functional monomer.

The hydrogel is obtained by free radical polymerization by using acrylamide as a main monomer, dopamine methacrylamide as a high-adhesion comonomer, double-bonded eugenol as a cross-linking agent and ammonium persulfate as an initiator.

Further, the method comprises the following steps:

mixing 10-30 parts of dopamine methacrylamide, 5-15 parts of double-bonded eugenol and 2400 parts of acetone solution in parts by mass, and fully stirring to obtain a solution A; dissolving 100-400 parts of acrylamide in 300-900 parts of neutral deionized water to obtain a solution B; and uniformly mixing the solution A and the solution B, adding 3-9 parts of ammonium persulfate, stirring for 30-60min, and fully reacting to obtain the ammonium persulfate/ammonium persulfate composite material.

The high-adhesion comonomer dopamine methacrylamide is obtained by introducing double-bond methacrylic anhydride into dopamine hydrochloride through amidation reaction.

The double-bonded eugenol is obtained by esterification reaction of biomass-based eugenol and methacrylic anhydride.

More specifically, the following steps may be included:

the method comprises the following steps: preparation of dopamine methacrylamide

According to the mass portion, 10-30 portions of sodium tetraborate and 4-12 portions of sodium bicarbonate are dissolved in 100 portions of deionized water and 300 portions of deionized water, then the mixture is placed in a reactor at 25 ℃, and N is introduced under the condition of good air tightness₂Reacting for 30-60min, adding 5-15 parts of dopamine hydrochloride into a reactor, slowly dropwise adding a mixed solution of methacrylic anhydride and tetrahydrofuran (in the process, dropwise adding 1mol/L sodium hydroxide aqueous solution to control the pH to be more than 8.0), and continuously introducing N₂Reacting for 14-18h, washing the generated suspension twice with ethyl acetate, then adjusting the pH to 1.0-3.0 with 6mol/L hydrochloric acid aqueous solution, extracting for 3 times with ethyl acetate, drying the three organic phases with anhydrous magnesium sulfate, filtering, adding the obtained filtrate into n-hexane for settling and stirring, standing overnight at 4 ℃, and drying in vacuum to obtain dopamine methacrylamide.

Step two: preparation of double-bonded eugenol

Adding 20-60 parts of eugenol into a reactor according to the mass fraction, and introducing N under the condition of good air tightness₂Reacting for 2-3h to remove O₂And moisture. Slowly dropping methacrylic anhydride into the reactor, gradually raising the temperature to 40-60 ℃, and continuously introducing N₂And reacting for 24 hours. The product from the reactor was transferred to a beaker, to which was added 2 to 4 volumes of dichloromethane to dilute the product. And adding a sodium bicarbonate aqueous solution with the volume 4 times that of the product into the beaker to wash the product with water, and repeatedly washing for 5-6 times until no bubbles are generated in the beaker. The organic layer in the beaker was washed with 1.0mol/L aqueous sodium hydroxide solution, 0.5mol/L aqueous sodium hydroxide solution, and 1.0mol/L hydrochloric acid solution in this order. Adding excessive anhydrous magnesium sulfate to dry the product, filtering, distilling under reduced pressure, and drying in an oven at 40-80 ℃ overnight to obtain the double-bonded eugenol.

Step three: preparation of double-bonded eugenol crosslinked mussel-imitated high-adhesion hydrogel.

Dissolving 10-30 parts of dopamine methacrylamide and 5-15 parts of double-bonded eugenol in 800-2400 parts of acetone solution by mass percent, and fully stirring until the dopamine methacrylamide and the double-bonded eugenol are completely dissolved to obtain a solution A; dissolving 100-400 parts of acrylamide in 300-900 parts of neutral deionized water to obtain a solution B; and mixing the solution A and the solution B, uniformly stirring, adding 3-9 parts of ammonium persulfate, stirring for 30-60min, and fully reacting to obtain the double-bonded eugenol crosslinked mussel-imitated high-adhesion hydrogel.

In the first step, the volume ratio of the methacrylic anhydride to the tetrahydrofuran mixed solution is 1: 5.

In the second step, the mass ratio of the eugenol to the methacrylic anhydride is 2: 1.

In the third step, solvents of dopamine methacrylamide and double-bonded eugenol are anhydrous acetone; the reaction temperature is 60-80 ℃, and the reaction time is 3-4 h.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) the invention provides a preparation method of a double-bonded eugenol crosslinked mussel-like hydrogel, wherein a method for copolymerizing dopamine methacrylamide, double-bonded eugenol and acrylamide is adopted in the preparation process, the double-bonded eugenol crosslinked mussel-like high-adhesion hydrogel can be obtained under mild conditions by adjusting the curing reaction conditions, and the used raw material acrylamide has the characteristics of low price, easiness in obtaining and wide application, and the preparation method is simple, the preparation conditions are mild, and the popularization and application prospects are realized.

(2) The double-bonded eugenol crosslinked mussel-like hydrogel prepared by the method utilizes good underwater adhesion of dopamine on one hand and reaction activity of unsaturated carbon-carbon double bonds in double-bonded eugenol on the other hand, so that the prepared hydrogel has good underwater adhesion and mechanical strength.

(3) The double-bonded eugenol crosslinked mussel-like hydrogel prepared by the invention can effectively regulate and control the adhesiveness and mechanical property of the gel by regulating the proportion of the adhesion functional monomer dopamine methacrylamide, the crosslinking agent double-bonded eugenol and a matrix acrylamide copolymerization system, and the hydrogel has better adhesiveness to aluminum plates, glass, polyethylene plastics, hardboards and birch boards in a water environment.

Detailed Description

The present invention will be described in detail with reference to specific embodiments. These examples are intended to further illustrate features and advantages of the present invention, and are not intended to limit the claims of the present invention.

The invention relates to a preparation method of double-bonded eugenol crosslinked mussel-imitated adhesive hydrogel, which takes acrylamide as a raw material, dopamine methacrylic anhydride as an adhesive functional monomer and double-bonded eugenol as a crosslinking agent to prepare the hydrogel with obviously improved underwater adhesive property and mechanical strength.