The synthesis of N-methylbis[2-(dodecylthio)ethyl]amine (SNS) and investigation of its efficiency as new mononuclear catalyst complex in copper-based ATRP

Abstract

This study is a report on atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a ligand, N-methylbis[2-(dodecylthio)ethyl]amine (SNS), which is tridentate ligand with mixed donor atoms. This ligand was synthesized in a simple way and at a low cost and was used to prepare a Cu catalyst complex (Cu/SNS) during the process of polymerization. The effects of various factors such as different molar ratios (100, 300, and 700 [monomer]:[initiator]) and cuprous halides (Br and Cl) on the polymerization of this ligand were investigated. The resulting catalyst complex mediated a living polymerization of MMA, yielding polymers with controlled molecular weights and narrow molecular weight distributions (1.09 < PDI < 1.4). The Highest PDI values were observed in the polymerization of the 700 molar ratio. The ligand, catalyst crystals formed at the end of polymerization, and synthesized polymers were characterized via UV-VIS, FTIR, CV, NMR, and GPC spectroscopy and single crystal X-ray crystallography as appropriate. The X-ray results for catalyst crystals showed that the catalyst was the deactivator (CuII Br2/SNS) of the ATRP equation and existed as a mononuclear catalyst complex.