CN113332936A

CN113332936A - High-toughness conductive anti-freezing carbon nanotube organic hydrogel

Info

Publication number: CN113332936A
Application number: CN202110747118.0A
Authority: CN
Inventors: 宋晓峰; 韩立彬; 沈月石; 魏君格; 曲瑞; 刘磊
Original assignee: Changchun University of Technology
Current assignee: Changchun University of Technology
Priority date: 2021-07-02
Filing date: 2021-07-02
Publication date: 2021-09-03

Abstract

The invention relates to a high-toughness freezing-conductive carbon nanotube organic hydrogel, wherein a hydroxylated multi-walled carbon nanotube (HO-MWCNT) is anchored on a polyvinyl alcohol (PVA) chain through hydrogen bond interaction to provide an effective conductive path, then Ammonium Persulfate (APS) is used as an initiator to initiate free radical polymerization of propionamide (AAm), vinyl acetate (VAc) and a chemical cross-linking agent N, N-Methylene Bisacrylamide (MBA), and a binary mixed solvent (dimethyl sulfoxide/water) is used as the organic hydrogel to realize freezing resistance. The prepared organic hydrogel shows excellent tensile strength, breaking point elongation and electric conductivity which are 561KPa, 2134 percent and 0.00312S-cm respectively^‑1Meanwhile, the freezing resistance is obviously improved, and the freezing point is-60 ℃.

Description

High-toughness conductive anti-freezing carbon nanotube organic hydrogel

Technical Field

The invention belongs to the field of hydrogel, and particularly relates to high-toughness conductive anti-freezing carbon nanotube organic hydrogel.

Background

The hydrogel is a three-dimensional network structure water expansion body formed by physical or chemical crosslinking, and has the advantages of flexibility, water-rich property, good biocompatibility and the like. The conductive hydrogel can simulate electronic skin, can be made into wearable electronic equipment and a flexible sensor, and has good application prospect in biomedicine and tissue engineering, but the hydrogel has poor mechanical property and is not resistant to extreme conditions, so that the application value of the conductive hydrogel is greatly limited. The development of robust, freeze resistant, electrically conductive hydrogels for use in human-computer interface devices is a novel direction.

The carbon nano tube is a novel nano material and has excellent electrical conductivity and mechanical property. Malleable and conductive hydrogels can be prepared by introducing carbon nanotubes into the hydrogel matrix, but the strongly hydrophobic carbon nanotubes are difficult to uniformly disperse in the hydrogel network to obtain a conductive hydrogel, which also leads to mechanical degradation. The introduction of hydrophilic groups can significantly improve the water solubility of the carbon nanotubes, and for example, the carbon nanotubes can be modified by oxidation to improve the dispersibility in the hydrogel. The carbon nano tube is integrated into the hydrogel with high performance, which has positive significance.

Disclosure of Invention

In order to overcome the defects of the traditional hydrogel, the invention provides a preparation method of a high-toughness, anti-freezing and conductive organic hydrogel. Compared with single solvent water, the binary solvent (water and DMSO) adopted by the invention obviously improves the frost resistance and solvent volatility resistance of the gel. The selected HO-MWCNT is anchored on a PVA chain through a hydrogen bond, so that the dispersibility is improved, and an effective electric path is formed in the organic hydrogel; in-situ free radical polymerization of AAm, VAc and MBA in PVA network to obtain large amount of-NH₂Can form hydrogen bonds with-OH on PVA chains, simultaneously comprises hydrogen bonds between PVA and PVA chains, hydrogen bonds between PAV and PAV chains, and-OH on hydroxylated multi-wall carbon nano-tubes and-OH in PVA and-NH in PAV network in organogel₂Hydrogen bonds formed between them, and also chemical cross-links formed in the PVA network as MBA.

Drawings

FIG. 1 is a stress-strain curve of an organic hydrogel.

Fig. 2 shows the conductivity versus freezing point.

Detailed Description

The invention is described in detail below by way of examples:

example 1:

adding 0.3g of PVA into a DMSO-water mixed solvent, fully dissolving at 110 ℃, cooling to room temperature, fully dissolving with 1.53g of AAm, 0.17g of VAc and 0.02g of MBA, adding 0.102g of APS, uniformly stirring, and ultrasonically degassing; and pouring the liquid into a mold, putting the mold into a 60 ℃ blast oven for reaction for 6h, cooling to room temperature, freezing at-20 ℃ for 24h, and unfreezing at room temperature to obtain the HO-MWCNT-free organic hydrogel.

Example 2:

adding 0.3g of PVA into a DMSO-water mixed solvent, fully dissolving at 110 ℃, cooling to room temperature, adding 0.5g of hydroxylated multi-wall carbon nano-tube containing 1.53g of AAm, 0.17g of VAc and 0.02g of MBA, fully dissolving, adding 0.102g of APS, uniformly stirring, and ultrasonically degassing; and pouring the liquid into a mold, putting the mold into a 60 ℃ blast oven for reaction for 6h, cooling to room temperature, freezing at-20 ℃ for 24h, and unfreezing at room temperature to obtain the HO-MWCNT organic hydrogel.

Claims

1. A high-toughness conductive anti-freezing carbon nanotube organic hydrogel is characterized in that:

(1) respectively taking polyvinyl alcohol (PVA), propionamide (AAm), vinyl acetate (VAc), N-Methylene Bisacrylamide (MBA) and hydroxylated multi-wall carbon nanotubes (HO-MWCNT) as raw materials, and (2) adding PVA into a dimethyl sulfoxide (DMSO)/water mixed solvent, fully dissolving at 110 ℃, cooling to room temperature, slowly adding weighed HO-MWCNT, then adding prepared mixed solution of AAm and VAc, adding APS, stirring uniformly, ultrasonically degassing, pouring the liquid into a mold, reacting at 60 ℃ for 6h, cooling to room temperature, freezing at-20 ℃ for 24h, and unfreezing at room temperature.

2. According to claim 1, not only AAm but also acrylic acid, hydroxyethyl methacrylate, hydroxyethyl acrylate and the like can be used.

3. According to claim 1, the VAc may be not only VAc but also methyl methacrylate, hydroxyethyl methacrylate, butyl methacrylate, or the like.

4. The process according to claim 1, wherein the mass ratio of the hydroxylated multi-walled carbon nanotubes to the initiator is 0.25:90:10:1: 5.

5. The step (2) according to claim 1, wherein the mass ratio of dimethyl sulfoxide to water is 6: 4.

6. The process (2) according to claim 1, wherein the ratio of the raw material to the solvent is 1: 9.

7. The method according to claim 1, wherein the step (3) is not limited to hydroxylated multi-walled carbon nanotubes, but may be carboxylated multi-walled carbon nanotubes, aminated multi-walled carbon nanotubes, graphene, reduced graphene oxide.