Preparation And Application Of Phytic Acid-Based Multifunctional Polyvinyl Alcohol Hydrogels

Hydrogels are water-rich three-dimensional network structures that play an important role in tissue engineering,electronic skin,and wearable sensing devices.However,traditional hydrogel systems are complex,low in strength and single in function,which seriously hinder the development and application of hydrogels.Therefore,hydrogel materials with simple preparation process,tunable properties and multifunctionality have always been one of the research hotspots.In this paper,a small molecule compound phytic acid（PA）and its derivatives sodium phytate（PANa）,borax（Borax）and biocompatible polyvinyl alcohol（PVA）,which are widely present in plants,are used as the main raw materials to prepare two kinds of hydrogel materials with different structures and functions were obtained,which provided new ideas for the application of hydrogels in different fields.Using the strong hydrogen bond between C-OH on the molecular chain of polyvinyl alcohol and P=O on the sodium phytate molecule and the coordination between sodium phytate and copper ions,a high-strength,high-toughness,high-sensitivity and hydrogel with photothermal conversion ability（Cu（II）-PVA/PANa gel）.Due to the higher crosslinking density,the hydrogel has higher strength and toughness than traditional hydrogels,and since Cu²⁺enhances the photothermal conversion ability of the hydrogel,based on the above properties,Cu（II）-PVA/PVA/PANa hydrogels are expected to be used in wearable sensing devices and photothermal diagnosis and treatment devices.By simply blending polyvinyl alcohol,phytic acid and borax,and using the borate bond of polyvinyl alcohol and borax as well as the hydrogen bond with phytic acid,the conductive hydraulic gel of PVA-PA-B"plasticine"was prepared.Based on the polyhydroxyl system of the hydrogel and the dynamics of the boronic ester bond,the prepared hydrogel exhibits extremely excellent self-healing,shear-thinning properties,adhesion,and stimuli-responsive properties.Based on its good adhesion and electrical conductivity,it can be assembled into wearable sensing devices,which can be directly attached to monitor human behavior and health status;based on its shear thinning and self-healing properties,the hydrogel can be applied for writing circuits;based on its pH-and sugar-responsive behavior,the hydrogel holds promise for remote switching.