Influence ofMEOBiPAcontent on the properties of novel photoluminescent thermosensitive hydrogels

Abstract

AbstractIn order to establish a dual functional hydrogel, a special monomer, methacryloyloxy‐ethylene‐oxy‐carbonyl bis[4‐(phenyl‐isopropyl)phenyl]amine (MEOBiPA), was prepared from bis[4‐(phenyl‐isopropyl)phenyl]‐4‐cyanophenyl amine and 2‐hydroxyethyl methacrylate. Subsequently, a series of thermosensitive hydrogels was obtained through copolymerization ofN‐isopropyl acrylamide (NIPAAm) withMEOBiPAbyUVirradiation (named theNMseries). The effect ofMEOBiPAcontent on the swelling behavior, mechanical properties and drug release behavior of the hydrogels was further investigated. Results showed that the swelling ratios of theNMcopolymeric hydrogels decreased from 4.73 to 1.74 g g−1when theMEOBiPAcontent in the hydrogel increased from 0.1 to 0.9 mol%. Both gel strength and crosslinking density of theNMhydrogels increased with increasingMEOBiPA. Conversely, the thermosensitive behavior ofNMhydrogels significantly decreased upon increase ofMEOBiPAcontent. Likewise, the caffeine release ratio also decreased from 70% to 25%. Notably, the intensity of photoluminescence increased with increasingMEOBiPAcontent in the hydrogels. Further, the corresponding copolymers of the hydrogels were prepared using free radical polymerization. TheUVabsorbance and photoluminescent behavior of theMEOBiPA,NIPAAm/MEOBiPAcopolymeric hydrogels and their corresponding copolymers in different polar solvents were also investigated. © 2015 Society of Chemical Industry