Preparation And Properties Of Oxidized Graphene / PDMAEMA Composite Hydrogel

Smart hydrogels with dramatic change of volume or other properties in responding to external stimuli have attracted much attention, because such hydrogel systems can serve as functional materials with potential applications in the areas of drug delivery, smart materials and environmental protection fields. 2-(Dimethylamino)ethyl methacrylate(PDMAEMA) hydrogels are multiple environmental responsive hydrogels, and graphene has been demonstrated to exhibit extraordinary physical properties when mixed with polymers to form nanocomposites. GO/PDMAEMA hybrid hydrogels prepared by in situ solution polymerization, play an increasingly important role in myriad applications, such as smart actuators.1. Graphene oxide(GO) was prepared according to modified Hummers method, which has abundant oxygen-containing surface functional groups. The structure and morphology of GO were characterized using FT-IR, UV, TGA, XRD, AFM, TEM,etc.2. The GO/PDMAEMA hybrid hydrogel sheets were fabricated by in situ UV-irradiation photopolymerization of monomer DMAEMA in the aqueous GO suspension. GO sheets in the hybrid hydrogels acted as not only a collaborative cross-linking agent but also as photoinitiator. The structure and morphology of hybrid hydrogel sheets characterized with the method of FT-IR, XRD, TGA, SEM,etc. We studied the mechanical properties and temperature sensitivity of hybrid hydrogel sheets by rheological test, and studied the swelling rate of hybrid hydrogel sheets to further to show volume changes in response to external stimuli such as temperature, pH, salt.3. By changing different external stimulus(such as temperature, pH, salt), we modulated both the in-plane and out of plane mismatches in mechanical properties to produce complex three-dimensional(3D) structures shape transformation from two-dimensional sheets. The GO/PDMAEMA hydrogel sheets could have good elastic properties and bending performance by environmental control successfully.