Well-defined PDMAEA stars via Cu(0)-mediated reversible deactivation radical polymerisation

The Cu(0)-mediated reversible deactivation radical polymerisation of N,N’-dimethylaminoethyl acrylate in DMSO and IPA at ambient temperature using Cu(0) wire is investigated. Tetra-functional and octa-functional initiators were utilised to facilitate the synthesis of well-defined PDMAEA star homo and block copolymers with a range of molecular weights (Mn ~ 5000-41000 g mol-1). Both solvents demonstrated to be excellent media for the controlled polymerisation of DMAEA yielding narrow molecular weight distributions (Ð ~ 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 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 (Ð < 1.19, Mn ~ 20000 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