A degradable atom transfer radical polymerization inimer: Synthesis, polymerization, and cleavage of the resulting polymer products

Abstract

A novel degradable inimer for atom transfer radical polymerization (ATRP), 2-(6-(2-((2-bromo-2-methylpropanoyl)oxy)ethyl)pyridin-2-yl)ethyl methacrylate (PyDEBrMΑ), was synthesized by the two-step esterification of 2,6-pyridinediethanol, first with α-bromoisobutyryl bromide in order to introduce the initiator moiety, and then with methacryloyl chloride in order to introduce the monomer moiety. PyDEBrMA was subsequently used to initiate the self-condensing ATRP of methyl methacrylate (MMA) to obtain a hyperbranched MMA homopolymer which could be cleaved at the PyDEBrMA residue either by treatment under mildly alkaline hydrolysis conditions (sodium deuteroxide in d6-DMSO at room temperature) or thermolysis at 150 °C. The lability of the PyDEBrMA residue arises from the presence in its structure of two 2-(pyridin-2-yl)ethyl ester moieties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2831–2839. © 2017 Wiley Periodicals, Inc.