ABSTRACT Electrochemically mediated atom transfer radical polymerizations (ATRPs) provide well‐defined polymers with designed dispersity as well as under external temporal and spatial control. In this study, 1‐cyano‐1‐methylethyl diethyldithiocarbamate, typically used as chain‐transfer agent (CTA) in reversible addition–fragmentation chain transfer (RAFT) polymerization, was electrochemically activated by the ATRP catalyst CuI/2,2′‐bipyridine (bpy) to control the polymerization of methyl methacrylate. Mechanistic study showed that this polymerization was mainly controlled by the ATRP equilibrium. The effect of applied potential, catalyst counterion, catalyst concentration, and targeted degree of polymerization were investigated. The chain‐end functionality was preserved as demonstrated by chain extension of poly(methyl methacrylate) withn‐butyl methacrylate and styrene. This electrochemical ATRP procedure confirms that RAFT CTAs can be activated by an electrochemical stimulus. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019,57, 376–381 
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                            Polymerization‐induced self‐assembly of metallo‐polyelectrolyte block copolymers
                        
                    
    
            ABSTRACT Cobaltocenium‐containing polyelectrolyte block copolymer nanoparticles were prepared via polymerization‐induced self‐assembly (PISA) using aqueous dispersion RAFT polymerization. The cationic steric stabilizer was a macromolecular chain‐transfer agent (macro‐CTA) based on poly(2‐cobaltocenium amidoethyl methacrylate chloride) (PCoAEMACl), and the core‐forming block was poly(2‐hydroxypropyl methacrylate) (PHPMA). Stable cationic spherical nanoparticles were formed in aqueous solution with low dispersity without adding any salts. The chain extension of macro‐CTA with HPMA was efficient and fast. The effects of block copolymer compositions, solid content, charge density, and addition of salts were studied. It was found that the degree of polymerization of both the stabilizer PCoAEMACl and the core‐forming PHPMA had a strong influence on the size of nanoparticles. © 2019 Wiley Periodicals, Inc. J. Polym. Sci.2020,58, 77–83 
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                            - Award ID(s):
- 1655740
- PAR ID:
- 10458011
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 58
- Issue:
- 1
- ISSN:
- 2642-4150
- Page Range / eLocation ID:
- p. 77-83
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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