Well-Defined PDMAEA Stars via Cu(0)-Mediated Reversible Deactivation Radical Polymerization

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• 作者：Richard Whitfield ; Athina Anastasaki ; Nghia P. Truong ; Paul Wilson ; Kristian Kempe ; James A. Burns ; Thomas P. Davis ; David M. Haddleton
• 刊名：Macromolecules
• 出版年：2016
• 出版时间：December 13, 2016
• 年：2016
• 卷：49
• 期：23
• 页码：8914-8924
• 全文大小：664K
• ISSN：1520-5835

文摘

The Cu(0)-mediated reversible deactivation radical polymerization of N,N′-dimethylaminoethyl acrylate in DMSO and IPA at ambient temperature using Cu(0) wire is investigated. Tetra- and octafunctional initiators were utilized to facilitate the synthesis of well-defined PDMAEA star homo and block copolymers with a range of molecular weights (M_n ∼ 5000–41 000 g mol^–1). Both solvents demonstrated to be excellent media for the controlled polymerization of DMAEA, yielding narrow molecular weight distributions (Đ ∼ 1.1) when the reactions were ceased at ∼40% conversion. Interestingly, at high conversions (typically >55%) high and low molecular weight shoulders were evident by SEC when DMSO and IPA were used, respectively, suggesting a large extent of termination and/or side reactions at prolonged reaction times. Nevertheless, high end group fidelity could be maintained when immediate precipitation of the polymers (at lower conversion) was performed, yielding low dispersed P(DMAEA-b-MA) star block copolymers (Đ < 1.19, M_n ∼ 20 000 g mol^–1). Importantly, guidelines on how to prevent hydrolysis, termination, and side reactions of PDMAEA as well as how to purify and store such materials are also provided and discussed.