Preparation And Investigation For Supramolecular Self-healing Hydrogel

Supramolecular hydrogel is a soft polymeric material composed of three dimensional network induced by non-covalent interactions.Compared to traditionally covalent ones,supramolecular hydrogel has many advantageous properties,especially self-healing property.In the research,we prepared a series of PVA-based hydrogel and investigated the property and potential application of as-prepared hydrogel.The main research works were described as follows:1.Self-healing supramolecular hydrogel of poly(vinyl alcohol)/chitosan carbon dotsWe concluded and modified the synthesis reported in the previous literature,successfully preparing the chitosan carbon dots(CDs).Then,CDs was homogeneously dispersed in PVA solution.Finally,PVA/CDs hydrogel was prepared using by freezing/thawing measurement.The result showed that self-healing behaviors of as-prepared hydrogel with 8 hours freezing time,12 hours selfhealing time and 0 hour separation time achieved the best;meanwhile,the thermal performance of the gel was also better than the pure poly(vinyl alcohol)hydrogel.PVA/CDs hydrogel also showed great fluorescence,indicating great potential application.2.Self-healing hydrogel of poly(vinyl alcohol)/graphite oxide with p H-sensitive and enhanced thermal propertyWe concluded the method presented in the previous literature,successfully obtaining the GO solution.Then,GO solution was dispersed in PVA solution.Finally,the PVA/GO hydrogel,using freezing/thawing experiment,was prepared.To investigate characterization and application,the asprepared PVA/GO supramolecular hydrogel was characterized.The result showed that with the increasing amount of GO,swelling ratio achieved peak at p H=7(a and b),p H=6(c)and p H=4(d);the thermal property gradually increased with the growing amount of GO,b and c sample are close;the self-healing behavior of b sample with 12 hours self-healing time and 0 hour separation time achieved the best.PVA/GO supramolecular hydrogel also showed great potential application in the field of ion and dye adsorption.3.Supramolecular hydrogel of poly(vinyl alcohol)/chitosan: A dual cross-link designWe investigated and summarized the method showed in the previous literature.Then,GO solution was dispersed in PVA/chitosan solution.Finally,the PVA/chitosan hydrogel,in the presence of GO,using freezing/thawing measurement,was obtained.The characterization of PVA/GO hydrogel was conducted.The result showed that the as-prepared hydrogel had p H responsiveness and temperature sensitivity,and the swelling absorption reached the peak at p H=7.5(T=25 ?)and T=40(p H=7.5),respectively;the self-healing equilibrium time gradually shortened with the increasing temperature and reached the 8 hours at 50 ?.