阅读说明：本技术 双网络柔性导电粘附抗冻水凝胶的制备方法和应用 (Preparation method and application of double-network flexible conductive adhesive anti-freezing hydrogel ) 是由 袁伟忠 周子璇 于 2021-04-07 设计创作，主要内容包括：双网络柔性导电粘附抗冻水凝胶的制备方法和应用,其双网络柔性导电粘附抗冻水凝胶可在常温和低温下直接粘附在皮肤上监测人类运动；其以聚乙烯醇(PVA)、植酸(PA)、[2-(甲基丙烯酰氧基)乙基]二甲基-(3-磺基丙基)氢氧化铵(SBMA)、聚丙烯酰胺(PAM)、NaCl和甘油为材料,PVA和PAM的双网络系统弥补了单网络水凝胶机械性能较差的缺点,PA与PVA的组合提高了水凝胶的拉伸性能,SBMA赋予了水凝胶的粘附性,NaCl和甘油的引入,可以提高复合水凝胶的导电和保水抗冻特性。同时,PA与PVA、甘油相互作用所形成的氢键还使得复合水凝胶有着自愈合的性能；制备方法简单,操作方便,并且材料来源“绿色”,制备出的复合水凝胶可重复使用。(The double-network flexible conductive adhesive antifreeze hydrogel can be directly adhered to skin at normal temperature and low temperature to monitor human movement; the composite hydrogel is prepared from polyvinyl alcohol (PVA), Phytic Acid (PA), 2- (methacryloyloxy) ethyl ] dimethyl- (3-sulfopropyl) ammonium hydroxide (SBMA), Polyacrylamide (PAM), NaCl and glycerol, wherein the PVA and PAM are used as materials, the double-network system makes up the defect of poor mechanical property of the single-network hydrogel, the combination of the PA and the PVA improves the tensile property of the hydrogel, the SBMA endows the hydrogel with adhesion, and the introduction of NaCl and glycerol can improve the conductivity, water retention and anti-freezing properties of the composite hydrogel. Meanwhile, the hydrogen bond formed by the interaction of the PA, the PVA and the glycerol also enables the composite hydrogel to have the self-healing performance; the preparation method is simple, the operation is convenient, the material source is green, and the prepared composite hydrogel can be repeatedly used.)

1. A preparation method of double-network flexible conductive adhesive anti-freezing hydrogel is characterized by comprising the following steps: which comprises the following steps:

(1) dissolving PVA and PA in deionized water, and stirring for 2 hours at 95 ℃ to obtain a uniform solution;

(2) adding SBMA and AM monomers into the solution, and stirring for 30min in an ice bath;

(3) adding a photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), a crosslinking agent N, N-Methylene Bisacrylamide (MBA) and NaCl into the solution, and magnetically stirring for 20 min;

(4) vacuum degassing the mixed solution obtained in the step (3), filling nitrogen, injecting into an organic glass mold, storing at the subzero temperature for 1h to form a first cross-linked network, thawing at room temperature for 2h, and then performing photopolymerization by ultraviolet (360nm) irradiation;

(5) and soaking the synthesized DN hydrogel slice into pure glycerol for solvent exchange to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

2. The method of claim 1, wherein: in the step (1), the mass ratio of PVA to PA is 1: 3-1: 10.

3. the method of claim 1, wherein: in the step (2), the mass ratio of SBMA to AM is 1: 1-4: 1.

4. the method of claim 1, wherein: in the step (3), the volume of the HHMP is 0.04-0.1mL, and the mass ratio of the MBA to the AM is 0.003: 1-0.01: 1, the mass ratio of NaCl to PVA is 0.01: 1-0.05: 1.

5. the method of claim 1, wherein: in the step (4), the subzero temperature is-20-0 ℃, and the ultraviolet irradiation time is 5-10 min.

6. The method of claim 1, wherein: in the step (5), the solvent exchange time is 25-45min, and the volume ratio of the glycerol to the water is 2: 1-4: 1.

7. a double-network flexible conductive adhesive anti-freezing hydrogel is characterized in that: which is obtained by the production method according to any one of claims 1 to 6.

8. Use of the double-network flexible conductive adhesive anti-freeze hydrogel according to claim 7 in wearable electronics and flexible sensors.

Technical Field

The invention belongs to the technical field of high polymer materials and flexible electronics, and particularly relates to a preparation method and application of a double-network flexible conductive adhesive anti-freezing hydrogel.

Background

In recent years, more researchers pay attention to the double-network hydrogel (DN), which exhibits significantly enhanced mechanical strength and self-healing capability due to its strong network entanglement and additional energy dissipation path, compared to the single-network hydrogel, because in the double-network, one network has a higher cross-linking density, is hard and brittle, has a relatively non-uniform structure, is prone to generate microcracks, and the other network has a lower cross-linking density, is soft and tough, and can transition and stabilize the microcracks generated in the first network and prevent the microcracks from combining with each other and developing into macroscopic cracks, so more researchers use the double-network hydrogel as a material for research and application.

Conductive hydrogels have been widely used in biomedical fields such as portable medical monitoring, electronic skin, human-computer interface, etc., where ion-conductive hydrogels have become a promising alternative material for retractable wearable devices due to their similar characteristics to biological tissues, such as softness, wettability, transparency, etc. Phytic Acid (PA) is a common natural product from plants, has a large number of hydroxyl groups and good ionization performance, can form hydrogen bond with a PVA chain, and weakens the crystallization behavior of the PVA. The PVA and the PAM form a double-network hydrogel system, the mechanical property of the hydrogel can be improved, the zwitterion [2- (methacryloyloxy) ethyl ] dimethyl- (3-sulfopropyl) ammonium hydroxide (SBMA) has good biocompatibility, ionic conductivity and adhesiveness, the self-adhesion effect can be realized, and the addition of the glycerol and the NaCl can endow the hydrogel with the anti-freezing and water-retaining effects, and simultaneously, the ionic conductivity of the hydrogel is increased.

Disclosure of Invention

Aiming at the defects in the prior art, the primary object of the invention is to provide a preparation method of a double-network flexible conductive adhesive antifreeze hydrogel

The second purpose of the invention is to provide the double-network flexible conductive adhesive antifreeze hydrogel.

The third purpose of the invention is to provide the application of the double-network flexible conductive adhesive anti-freezing hydrogel.

In order to achieve the above purpose, the solution of the invention is as follows:

a preparation method of a double-network flexible conductive adhesive antifreeze hydrogel comprises the following steps:

(1) dissolving PVA and PA in deionized water, and stirring for 2 hours at 95 ℃ to obtain a uniform solution;

(2) adding SBMA and AM monomers into the solution, and stirring for 30min in an ice bath;

(3) adding a photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), a crosslinking agent N, N-Methylene Bisacrylamide (MBA) and NaCl into the solution, and magnetically stirring for 20 min;

(4) vacuum degassing the mixed solution obtained in the step (3), filling nitrogen, injecting into an organic glass mold, storing at the subzero temperature for 1h to form a first cross-linked network, thawing at room temperature for 2h, and then performing photopolymerization by ultraviolet (360nm) irradiation;

(5) and soaking the synthesized DN hydrogel slice into pure glycerol for solvent exchange to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

Preferably, in the step (1), the mass ratio of PVA to PA is 1: 3-1: 10.

preferably, in the step (2), the mass ratio of SBMA to AM is 1: 1-4: 1.

preferably, in step (3), the volume of HHMP is 0.04-0.1mL, and the mass ratio of MBA to AM is 0.003: 1-0.01: 1, the mass ratio of NaCl to PVA is 0.01: 1-0.05: 1.

preferably, in the step (4), the subzero temperature is-20-0 ℃, and the ultraviolet irradiation time is 5-10 min.

Preferably, in the step (5), the solvent exchange time is 25-45min, and the volume ratio of the glycerol to the water is 2: 1-4: 1.

a double-network flexible conductive adhesive anti-freezing hydrogel is prepared by the preparation method.

The double-network flexible conductive adhesive anti-freezing hydrogel can be applied to artificial intelligence and flexible electronic technology.

Due to the adoption of the scheme, the invention has the beneficial effects that:

firstly, the flexible conductive adhesive anti-freezing hydrogel disclosed by the invention is a double-network system, so that the defects of a single-network hydrogel are overcome, and the flexible conductive adhesive anti-freezing hydrogel can still keep good mechanical properties after being used for many times. And natural materials are combined into the hydrogel, and ions are utilized for conducting, so that the prepared double-network hydrogel integrates biocompatibility, transparency, high mechanical property, high conductivity and viscosity, and has wide application prospects in the aspects of flexible wearable equipment, intelligent artificial skin and the like.

Secondly, the double-network flexible conductive adhesive anti-freezing hydrogel disclosed by the invention has good anti-freezing and water-retaining properties, and the hydrogel can normally work under severe conditions (such as low temperature and drying) due to the addition of the glycerol and the NaCl, so that the working range of the hydrogel is greatly expanded.

Thirdly, the preparation method of the double-network flexible conductive adhesive antifreeze hydrogel is simple and convenient to operate, and the prepared double-network flexible conductive adhesive antifreeze hydrogel has good self-healing performance and can be repeatedly used.

Detailed Description

The invention provides a preparation method and application of a double-network flexible conductive adhesive antifreeze hydrogel, which can be directly adhered to skin at normal temperature and low temperature to monitor human movement; the invention takes polyvinyl alcohol (PVA), Phytic Acid (PA), 2- (methacryloxy) ethyl ] dimethyl- (3-sulfopropyl) ammonium hydroxide (SBMA), Polyacrylamide (PAM), NaCl and glycerol as materials, the double-network system of PVA and PAM makes up the defect of poor mechanical property of single-network hydrogel, the combination of PA and PVA improves the tensile property of the hydrogel, the SBMA endows the hydrogel with adhesiveness, and the introduction of NaCl and glycerol can improve the electric conduction, water retention and anti-freezing properties of the composite hydrogel. Meanwhile, the hydrogen bond formed by the interaction of the PA, the PVA and the glycerol also enables the composite hydrogel to have the self-healing performance; the preparation method of the double-network flexible conductive adhesive anti-freezing hydrogel is simple and convenient to operate, the material source is green, and the prepared composite hydrogel can be reused.

The present invention will be further described with reference to the following examples.

Example 1:

the preparation method of the double-network flexible conductive adhesive antifreeze hydrogel comprises the following steps:

(1) dissolving 3g of PVA and 9gPA in 10mL of deionized water, and stirring at 95 ℃ for 2h to obtain a uniform solution;

(2) adding 2g of SBMA and 2g of AM monomers into the solution, and stirring for 30min under an ice bath;

(3) 0.04mL of photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), 6mg of crosslinker N, N-Methylenebisacrylamide (MBA) and 0.03g of NaCl were added to the solution and stirred magnetically for 20 min;

(4) degassing the mixed solution obtained in the step (3) in vacuum, filling nitrogen, injecting into an organic glass mold, preserving at-20 ℃ for 1h to form a first cross-linked network, thawing for 2h at room temperature, and then irradiating for 5min by ultraviolet rays (360nm) to carry out photopolymerization;

(5) and soaking the synthesized DN hydrogel slice into 20mL of pure glycerin for solvent exchange for 25min to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

In the preparation process of the embodiment, PVA and PAM form a double-network structure to improve the mechanical property of the hydrogel, and meanwhile, a green material PA and a self-adhesive zwitter ion SBMA are introduced to improve the biocompatibility, the adhesion and the conductivity of the hydrogel, and the hydrogel has good water retention, frost resistance and ionic conductivity due to the existence of glycerol and NaCl. The addition of these materials greatly enriches the various properties of the composite hydrogel.

FIG. 1 shows the tensile curve of a double-network flexible conductive adhesive antifreeze hydrogel, as shown in FIG. 2, the hydrogel has good elongation at break (655%) and strength at break (375kPa), showing the good mechanical properties of the hydrogel.

Figure 2 shows the electrical conductivity properties of the hydrogel. As shown in FIG. 2, when hydrogel is connected into the circuit of the small bulb, the small bulb can be lighted, and the hydrogel is twisted and deformed, the small bulb can still emit bright light, which shows that the prepared hydrogel has stable conductivity.

Figure 3 shows the adhesion properties of the hydrogel. The hydrogel can be adhered to the surfaces of various materials, such as nitrile gloves, glass, plastics and rubber, and shows that the hydrogel has good adhesion performance.

Example 2:

the preparation method of the double-network flexible conductive adhesive antifreeze hydrogel comprises the following steps:

(1) dissolving 2g of PVA and 20gPA in 10mL of deionized water, and stirring at 95 ℃ for 2h to obtain a uniform solution;

(2) adding 4g of SBMA and 1g of AM monomer into the solution, and stirring for 30min under an ice bath;

(3) 0.01mL of photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), 10mg of crosslinker N, N-Methylenebisacrylamide (MBA) and 0.1g of NaCl were added to the solution and stirred magnetically for 20 min;

(4) degassing the mixed solution obtained in the step (3) in vacuum, filling nitrogen, injecting into an organic glass mold, preserving at 0 ℃ for 1h to form a first cross-linked network, thawing at room temperature for 2h, and then irradiating by ultraviolet rays (360nm) for 10min for photopolymerization;

(5) and soaking the synthesized DN hydrogel slice into 40mL of pure glycerin for solvent exchange for 45min to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

Example 3:

the preparation method of the double-network flexible conductive adhesive antifreeze hydrogel comprises the following steps:

(1) dissolving 3g of PVA and 10gPA in 15mL of deionized water, and stirring at 95 ℃ for 2h to obtain a uniform solution;

(2) adding 2g of SBMA and 2g of AM monomers into the solution, and stirring for 30min under an ice bath;

(3) 0.06mL of photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), 6mg of crosslinker N, N-Methylenebisacrylamide (MBA) and 0.03g of NaCl were added to the solution and stirred magnetically for 20 min;

(4) degassing the mixed solution obtained in the step (3) in vacuum, filling nitrogen, injecting into an organic glass mold, preserving at-15 ℃ for 1h to form a first cross-linked network, thawing at room temperature for 2h, and then irradiating by ultraviolet rays (360nm) for 10min for photopolymerization;

(5) and soaking the synthesized DN hydrogel slice into 30mL of pure glycerin for solvent exchange for 30min to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

Example 4:

the preparation method of the double-network flexible conductive adhesive antifreeze hydrogel comprises the following steps:

(1) dissolving 3g of PVA and 15gPA in 10mL of deionized water, and stirring at 95 ℃ for 2h to obtain a uniform solution;

(2) adding 2g of SBMA and 2g of AM monomers into the solution, and stirring for 30min under an ice bath;

(3) 0.08mL of photoinitiator 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylacetophenone (HHMP), 6mg of crosslinker N, N-Methylenebisacrylamide (MBA) and 0.03g of NaCl were added to the solution and stirred magnetically for 20 min;

(4) degassing the mixed solution obtained in the step (3) in vacuum, filling nitrogen, injecting into an organic glass mold, preserving at-10 ℃ for 1h to form a first cross-linked network, thawing for 2h at room temperature, and then irradiating for 5min by ultraviolet rays (360nm) to carry out photopolymerization;

(5) and soaking the synthesized DN hydrogel slice into 25mL of pure glycerin for solvent exchange for 40min to obtain the double-network flexible conductive adhesive anti-freezing hydrogel.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. It will be readily apparent to those skilled in the art that various modifications to these embodiments and the generic principles defined herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above-described embodiments. Those skilled in the art should appreciate that many modifications and variations are possible in light of the above teaching without departing from the scope of the invention.