Synthesis, self-assembly and responsive properties of PEG- b-PDMAEMA- b-PMMAzo triblock copolymers.

A novel amphiphilic copolymer poly(ethylene glycol)- block-poly( N, N-dimethylamino-2-ethylmethacrylate)- blockpoly[6-(4-methoxy-azobenzene-4′-oxy) hexyl methacrylate] (PEG- b-PDMAEMA- b-PMMAzo) was prepared by ATRP polymerization. The self-assembly and responsive behaviors were investigated by SEM, TEM, LLS and UV-Vis spectra. The results indicated that the copolymers can self-assemble into spherical structures in aqueous media. The aggregate size can be tuned by pH and temperature. The trans- cis isomerization behavior of the formed aggregates was also examined. Upon irradiation with a linear polarized light, the elongation degree of the aggregates was increased with the irradiation time. [ABSTRACT FROM AUTHOR]