Preparation And Characterization Of High Strength Graphene Oxide Nanocomposite Hydrogel

Hydrogel has been used widely in daily life,what's more,it has broad potential applications in bio-engineering,water pollution treatment,sensors and smart materials,which has been waiting to be explored.However,the development of practical application of hydrogel is seriously blocked by the its weak mechanical properties.Herein,using graphene oxide as physical cross-linking agent,and combining the mechanism of nanocomposite hydrogel with double network hydrogel,dual cross-linking hydrogel and supermolecular hydrogel,two different kinds of high strength graphene oxide nanocomposite hydrogel have been synthesized.And the following is the main content.1?Agar/polyacrylamide-graphene oxide(agar-PAM/GO)double network nanocomposite hydrogel was synthesized using GO as the physical cross-linking agent,and agar nature molecular and acrylamide(AM)as hydrogel monomers.For agar-PAM/GO hydrogel,agar molecular which formed the first network was cross-linked via hydrogen bonds,and the PAM chains adsorbed on the GO sheets forming the second network.The agar-PAM/GO hydrogel possessed favorable tensile properties,the fracture strength was about 332 k Pa and the fracture strain was about 4600%;according to its unique necking phenomenon,the fracture mechanism of agar-PAM/GO hydrogel was explored;the cut hydrogel could be self-healed with a self-heal efficiency of 48%.2 ? According to the mechanism of dual cross-linking hydrogel and host-gust supermolecular hydrogel,using graphene oxide as physical cross-linking agent,and ?-cyclodextrain(?-CD),poly(ethylene glycol)methyl ether methacrylate(PEGMA)and AM as materials,the P(AM-co-PEGMA)/GO/CD dual cross-linking nanocomposite hydrogel was synthesized.For the P(AM-co-PEGMA)/GO/CD hydrogel,the polymer main chains adsorbed on the GO sheets forming the first cross-linking system,and the rotaxanes composed of ?-CD and PEGMA contacted with each other closely via the hydrogen bonds between ?-CDs,which formed the second cross-linking system.The P(AM-co-PEGMA)/GO/CD hydrogel possessed a fracture strength of 660 kPa and fracture strain of 1800%,and it was found that the molar ratio of ?-CD to PEGMA had an outstanding effect on the mechanical properties of the hydrogel;in addition,the hydrogel had a good thermoplastic ability and the reshaped hydrogel's strength was almost same with that of the original hydrogel;in addition,the thermal responsive shape memory behavior of the P(AM-co-PEGMA)/GO/CD hydrogel was also explored.