Self-assembly and Photoresponsive Properties of Amphiphillic Polymers Based on Itaconic Acid with Pendant Azobenzene Mesogenic Moieties

In this work, pH- responsive micelles of a series of azobenzene-functionalized poly (monomethyl itaconate) (PMMI) with various amounts of azobenzene substitutions (PMMI-Azo) were prepared by solvent evaporation and dialysis methods. The polymers were prepared through the esterification reaction of PMMI with 4-hydroxy-4′- ethoxyazobenzene. The degree of substitution with the azobenzene moieties (DSazo) can be adjusted by changing the feed ratio in the reaction mixture. Stability and pH-responsive property of the micelles were studied by both UV-Visspectroscopy. The trans-to-cis photo-isomerization properties of PMMI-Azo polymers with UV and visible light in solution were investigated. These photo-responsive micelles self-assembled from amphiphilic polymers might have great potential in various practical applications such as controlled drug release

Keywords:

amphiphilc homopolymers , liquid-crystal , side chain polymers , azo polymers