Synthesis of cationic star polymers by simplified electrochemically mediated ATRP

Abstract

Abstract. Cyclodextrin-based cationic star polymers were synthesized using β-cyclodextrin (β-CD) core, and 2-(dimethylamino)ethyl methacrylate (DMAEMA) as hydrophilic arms. Star-shaped polymers were prepared via a simplified electrochemically mediated ATRP (seATRP) under potentiostatic and galvanostatic conditions. The polymerization results showed molecular weight (MW) evolution close to theoretical values, and maintained narrow molecular weight distribution (MWD) of obtained stars. The rate of the polymerizations was controlled by applying more positive potential values thereby suppressing star-star coupling reactions. Successful chain extension of the ω-functional arms with a hydrophobic n-butyl acrylate (BA) formed star block copolymers and confirmed the living nature of the β-CD-PDMAEMA star polymers prepared by seATRP. Novelty of this work is that the β-CD-PDMAEMA-b-PBA cationic star block copolymers were synthesized for the first time via seATRP procedure, utilizing only 40 ppm of catalyst complex. The results from 1 H NMR spectral studies support the formation of cationic star (co)polymers.

Synthesis of Well‐Defined Polymer Brushes from Silicon Wafers via Surface‐Initiated se ATRP

“…At the beginning of the electrolysis, only deactivator (X−Cu II /L) was present in the reaction mixture, so the cathodic current decayed as X−Cu II /L was converted to the Cu I /L activator. Subsequently, the current approached a low and constant value as the [X–Cu II /L]/[Cu I /L] ratio, adjusted by the selected E app , was obtained . A more negative potential generated larger initial value of the current indicating a higher reduction rate (Figure S2b, Supporting Information) and thus faster polymerization (compare k p app ; Table , entries 1−4; Figure b).…”

“…Recently, a simplified electrochemically mediated ATRP ( se ATRP) was developed, a procedure which does not require the separation of cathodic and anodic compartments in the e ATRP reactor . The use of an undivided cell allowed for a simpler reaction setup and lower cost of the process.…”

“…[37,39] Recently, a simplified electrochemically mediated ATRP (seATRP) was developed, a procedure which does not require the separation of cathodic and anodic compartments in the eATRP reactor. [33,35,[40][41][42][43][44] The use of an undivided cell allowed for a simpler reaction setup and lower cost of the process. The system was further simplified by working under galvanostatic conditions using a two-electrode system directly powered by a current generator.…”

Synthesis of Riboflavin‐Based Macromolecules through Low ppm ATRP in Aqueous Media

“… a) Monomer conversion, apparent propagation constants ( k p app ), and apparent degree of polymerization of monomer unit per chain (DP n,theo ) were determined by NMR; …”

Synthesis of inositol‐based star polymers through low ppm ATRP methods

“…Monomer conversion, apparent propagation constants ( k p app ), and apparent degree of polymerization of monomer unit per arm (DP n,theo ) were determined by NMR. ()…”