Preparation of polyurethane hydrogels based on polyethylene glycol/ ε-caprolactone/ methylene diphenyl diisocyanate in the presence of graphene oxide nanoplatelets

Polymeric hydrogels are tridimensional polymeric networks, capable of absorbing a high amount of water.1 Due to their water uptake capacity, potential amphiphilic behavior, and biocompatibility or biodegradability, hydrogels have been intensively studied for applications in the biomedical, pharmaceutical, agriculture, oil recovery, and cosmetics fields as well as in the biotechnology, bioseparation processes, and as biosensors.2,3 In this work, graphene oxide nanoplatelets (GNP's) were homogeneously trapped into a polyurethane (PU)-based hydrogel during its preparation (Fig. 1). The effect of the nanoparticles on the thermal behavior as well as the amounts of water uptake were thoroughly studied. Briefly, an azide-containing and polyoxyethylene (PEG)-based polyurethane (PU) was synthesized starting from PEG, ɛ-caprolactone (ɛ-CL), and methylene diphenyl diisocyanate (MDI). Next, dialkynyl PEG was used as the crosslinker in the presence of GNP's in 0.1, 0.2, and 0.5 wt.%. In this stage, a thermally-induced copper (I)-catalyzed 1,3-dipolar azide-alkyne cycloaddition (CuAAC) was performed. FT-IR, XRD, 1H-NMR and FE-SEM techniques were used to characterize the samples obtained

کلیدواژه ها:

Polymeric networks ، Polyurethane hydrogels ، Graphene oxide nanoplatelets