Preparation of Light‐Responsive Polyester Micelles via Ring‐Opening Polymerization of O‐Carboxyanhydride and Azide–Alkyne Click Chemistry

Abstract

Reversibly light‐responsive micelles are constructed from an amphiphilic azobenzene‐containing diblock copolymer AZO‐mPEG‐poly(5)25. The copolymer is synthesized via ring‐opening polymerization of O‐carboxyanhydrides bearing alkyne group, followed by azide–alkyne click chemistry with an azide‐containing azobenzene derivative. AZO‐mPEG‐poly(5)25 can self‐assemble to spherical micelles. Light response of the polymeric micelles is demonstrated by UV–vis spectroscopy and scanning electron micro­scopy (SEM). SEM images show that after UV irradiation, the micelles are partly dissociated, which is ascribed to swelling of the hydrophobic chain because of hydrophobicity change during the trans–cis isomerization of the azobenzene group. After subsequent visible‐light irradiation, the morphology returns back to micelles. image