A Schiff base ligand for photoinduced atom transfer radical polymerization

Abstract

A claw-type Schiff base, tris[N-(2-pyridylmethyl)-2-iminoethyl]amine (Py₃Tren), is used as an active ligand for photoinduced atom transfer radical polymerization (Photo-ATRP). CuBr₂/Py₃Tren was employed as a catalyst for Photo-ATRP of methyl methacrylate (MMA) under the irradiation of ultraviolet or visible light. Well-defined poly(MMA) could be synthesized with high chain-end functionality confirmed by in situ chain extension. Temporal control of Photo-ATRP was successfully demonstrated by switching the light on and off. The polymerization mechanism was finally discussed through UV/vis spectroscopy and electrospray ionization mass spectrometry (ESI-MS) experiments.