Chemical engineering LCST N-isopropylacrylamide OEGylated RAFT Technology: general issues UCST polymers Ugi reaction aggregation aqueous solutions aza-Michael addition reaction biodegradable polymer block and gradient copolymers of poly-2-alkyl-2-oxazolines calix[n]arene coil to globule conformation controlled release dual-stimuli-responsive materials electronic paramagnetic resonance emulsion polymerization enzyme complexation glycidyl methacrylate hydrogels light scattering microcalorimetry nitroxides oligo(ethylene glycol) out-of-equilibrium pH-responsive phase diagram