The influence of monomer/solvent feed ratio on POEGDMA thermoresponsive hydrogels: Radiation-induced synthesis, swelling properties and VPTT

摘要

The oligo(ethylene glycol) dimethacrylate (OEGDMA), one of the most commonly utilized crosslinking monomers, was used to tailor thermoresponsive POEGDMA hydrogels by varying the monomer/solvent feed ratio (from 10 to 100 wt% of monomer). For the first time, synthesis of different POEGDMA homopolymeric networks was performed by gamma radiation, and due to the expected thermoresponsiveness their temperature-dependent properties were extensively analysed. The sol-gel study was performed as the first step after radiation-induced synthesis. The swelling properties were investigated over the wide pH (2.2-9.0) and temperature (5-80 degrees C) range. Characterization of structure and properties was additionally conducted by SEM, DSC, FTIR, and UV-Vis spectroscopy. The results indicated that all POEGDMA hydrogels showed a high gel content, inverse thermoresponse and volume phase transition temperature (VPTT) with no respect to initial preparation. On the other hand, by altering the monomer/solvent ratio in the prepolymerisation mixture a large diversity in the micro-structure, swelling capacity and VPTT was obtained.