Tetra-PEG-Based Nano-Enhanced Hydrogel with Excellent Mechanical Properties and Multi-Functions

Further improving mechanical performances of the tetra-PEG hydrogel and simultaneously endowing it with functionalities remains a challenge. Herein, rGO is introduced into the tetra-PEG network to construct a tetra-PEG/rGO nanocomposite (NC) hydrogel with improved mechanical performances and functionalities. The hydrogel is prepared by in situ simultaneous polymerization of clickable tetra-PEG macromonomers (TAPEG and TPPEG) and reduction of GO in one pot. The amount of rGO introduced into the hydrogel network is determined and can be controlled through tuning the feed ratio of the GO to the macromonomers. The tetra-PEG/rGO NC hydrogel displays drastically improved mechanical performances including tensile properties, compressive properties, and fatigue resistance compared to the pristine clickable tetra-PEG hydrogel. SEM, FT-IR, and loading-unloading experiments indicate that interactions between rGO sheets and tetra-PEG segments contribute to the mechanical improvement. Furthermore, the tetra-PEG/rGO NC hydrogel exhibits selective dye adsorption ability and near-infrared light responsiveness. The tetra-PEG/rGO NC hydrogel with excellent mechanical performances and functionalities is highly promising in many areas such as dye absorption, remote light-controlled devices, and tissue engineering.