Multi-responsive (diethylene glycol)methyl ether methacrylate (DEGMA)-based copolymer systems

Multi-responsive (diethylene glycol) methyl ether methacrylate-methacrylic acid (DEGMA-MAA) copolymers were synthesised for the first time via RAFT polymerisation, and the structure-activity interplay of statistical and block copolymers in solution was compared. In addition to MAA, DEGMA was also copolymerised with 2-(dimethylamino)ethyl methacrylate (DMAEMA) to generate two sets of well-defined weakly acidic or weakly basic copolymers, respectively. The temperature, pH and salt-responsive properties of all polymers was determined via UV-visible spectroscopy and dynamic light scattering, and their solution structures as a function of temperature were visualised via electron microscopy. Results from this study indicate that the DEGMA-MAA statistical and block copolymers display similar stimuli-responsive property trends to the well-characterised DEGMA-DMAEMA copolymers, and show similar lower critical solution temperature (LCST) modulations and aggregate structures in water.