A series of star-shaped poly(ε-caprolactone) (PCL)-based diblock and triblock copolymerscontaining 2-(Dimethylamino)ethyl methacrylate (DMAEMA or DMA) and oligo(ethylene glycol)monomethyl ether methacrylate (OEGMA or OEG) were synthesized in one pot by atom transfer radical polymerization (ATRP) using a six-arm PCL-based macroinitiator. The precursor and the resultant copolymers were characterized via 1H NMR and size exclusion chromatography (SEC). The monomer reactivity ratios for DMAEMA (r1) and OEGMA (r2) were estimated to be near unity and r1×r2 = 1, indicating the random distribution of the monomers in the final copolymers. Self-assembly behavior of these copolymers was investigatedby fluorimetry, 1H NMR, DLS, TEM, potentiometric titrations and zeta potential measurements.The results suggested that the star copolymers were responsive to salinity depending on their composition and structure.
