Dual Stimuli Switching: Interconverting Cationic and Radical Polymerizations with Electricity and Light

Abstract

Block polymers, macromolecules consisting of two or more regions of unique monomer composition with complex structures are important materials in the development of new technologies. Multiblock polymers can provide unique physical properties on the basis of monomer choice, block length, and the number of polymer blocks. Traditional approaches for generating multiblock copolymers are often arduous, multistep syntheses. We present a facile method where higherorder multiblock copolymers can be synthesized in situ by interconverting the polymerization mechanism using light and electricity.

Mixed Polymer Brushes for “Smart” Surfaces

“…This orthogonal approach has found increasing adoption in solution polymerization [135][136][137] and can also provide possibilities to polymerize either chain end selectively as a function of external stimulation [138][139][140]. Recent research also shows how it is possible to reversibly switch between multiple mechanisms [141][142][143][144][145]. Nonetheless, for MPB synthesis, there exist only limited studies that leverage this orthogonal approach.…”

Hydrogen Bond Donor Catalyzed Cationic Polymerization of Vinyl Ethers

“…However, developing polymerization methods with living characteristics is challenging and often requires specialized reagents and reaction conditions. Specifically, living cationic processes often require rigorously dried solvents, cold temperatures, and additives to avoid deleterious termination and chain transfer events [2–16] . Therefore, designing a robust controlled cationic polymerization under mild conditions that can produce high‐molecular‐weight polymers remains a challenge.…”

“…Specifically, living cationic processes often require rigorously dried solvents, cold temperatures, and additives to avoid deleterious termination and chain transfer events. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Therefore, designing a robust controlled cationic polymerization under mild conditions that can produce high-molecular-weight polymers remains a challenge.…”

Making Block Copolymers with the Flip of a Switch

“…8 In this issue of Chem, Fors and coworkers creatively overcome the limitations of this previous work by employing an electrochemical stimulus to control the cationic polymerization of vinyl ethers (Figure 1). 9 First, their electrochemically mediated cationic RAFT (cationic eRAFT) method 10 is adapted for compatibility with an orthogonal radical polymerization. 9 Whereas previous work employed 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)-a known radical trap-as a redox mediator, 10 this work instead uses ferrocene.…”

“…9 First, their electrochemically mediated cationic RAFT (cationic eRAFT) method 10 is adapted for compatibility with an orthogonal radical polymerization. 9 Whereas previous work employed 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)-a known radical trap-as a redox mediator, 10 this work instead uses ferrocene. After demonstrating that isobutyl vinyl ether (IBVE) can be polymerized in a controlled fashion by using this new redox mediator and a dithiocarbonyl chain-transfer agent (CTA), the compatibility of this polymerization system with a radical polymerization is evaluated.…”