Starch-based physical crosslinking hydrogel as well as preparation method and application thereof

Abstract

The invention relates to starch-based physical crosslinking hydrogel as well as a preparation method and application thereof. The preparation method of the starch-based physical crosslinking hydrogel comprises the following steps: 1) mixing natural starch, polyvinyl alcohol and ultrapure water, sealing, heating in a water bath, and stirring until the natural starch and the polyvinyl alcohol are completely dissolved to obtain sol A; (2) adding 1-ethyl-3-methylimidazole acetate into the sol A, and heating and stirring for a certain time to obtain sol B; 3) adding aluminum chloride into the sol B, heating and stirring until the aluminum chloride is completely dissolved to obtain sol C; and 4) heating the sol C for a period of time, removing bubbles in the sol C, pouring the sol C into a mold, circularly freezing and thawing, and demolding to obtain the product. The starch-based physical crosslinking hydrogel prepared by the invention has the properties of antibiosis, high flexibility, high conductivity and the like, and is very suitable for being applied to the fields of flexible wearable sensors, electronic skin, tissue engineering or wound dressings.

Description

technical field [0001] The invention relates to the field of bio-based polymer functional materials, in particular to a starch-based physical cross-linked hydrogel and a preparation method and application thereof. Background technique [0002] Hydrogel is a kind of hydrophilic polymer material with three-dimensional network structure. Because of its good flexibility, biocompatibility, ion transport ability and other advantages, it is widely used in flexible wearable sensors, electronic skin, tissue engineering and wounds. Dressings and other fields have important application potential. At present, most hydrogels are formed by chemical cross-linking of traditional petroleum derivatives. With the shortage of resources and the increasingly prominent environmental problems, it is imperative to develop flexible "green" physically cross-linked hydrogels. [0003] Starch is one of the most abundant natural polymers, with the characteristics of renewability, low cost, biocompatibil...

AI Technical Summary

Problems solved by technology

However, the stretchability and electrical conductivity of pure starch hydrogel are poor. At present, it is more effective to improve the above properties by combining starch with polyvinyl alcohol (polyvinyl alcohol) to form a double-network hydrogel and adding conductive materials. However, due to the large difference in the molecular structure of starch and polyvinyl alcohol, the compatibility between starch and polyvinyl alcohol is poor, it is necessary to add a plasticizer to improve the compatibility of the two, and then improve the uniformity of the gel network

[0004] In the prior art, people such as Wang have prepared starch / polyvinyl alcohol / borax hydrogel, but its tensile strength (5.5kPa) and electrical conductivity (1S m -1 ) were lower, (Y.Wang, H.Huang, J.Wu, L.Han, Z.Yang, Z.Jiang, R.Wang, Z.Huang, M.Xu, Ultrafast self-healing, reusable, and conductivepolysaccharide -basedhydrogels forsensitive ionic sensors, ACSSustain.Chem.Eng.8(2020)18506-18518.); Lu et al. combined glycerol and CaCl 2 Introduced into a starch / polyvinyl alcohol mixture, a stretchable, freeze-resistant and thermoplastic hydrogel was prepared (J.Lu, J.Gu, O.Hu, Y.Fu, D.Ye, X.Zhang , Y.Zheng, L.Hou, H.Liu, X.Jiang, Highly tough, freezing-tolerant, healable and thermoplastic starch / poly(vinyl alcohol) organohydrogels for flexible electronic devices, J.Mater.Chem.A9(2021) 18406-18420 .), but due to the use of organic solvents, the conductivity (1S m -1 ) is still low

Images