Supplemental Activator and Reducing Agent Atom Transfer Radical Polymerization of 2‐Hydroxyethyl Acrylate from High Molar Mass Poly(ethylene oxide) Macroinitiator in Dilute Solution

Abstract

Triple hydrophilic asymmetric poly(2-hydroxyethyl acrylate)-b-poly(ethylene oxide)-b-poly(2-hydroxyethyl acrylate) (PHEA-b-PEO-b-PHEA) triblock copolymers are obtained by copper(0) catalyzed reversible deactivation radical polymerization (RDRP). Copper wire catalyzed polymerization of HEA from large PEO ( M n = 35 000 g mol −1 ) macroinitiator in dimethylsulfoxide or in water fails to reach high monomer conversion in a controlled manner contrary to what is previously published with a shorter PEO macroinitiator. Catalysis by nascent Cu(0) particles generated by disproportionating CuBr in water allows rapid polymerization and high monomer conversion with a rather good control of both dispersity and HEA block length. Model disproportionation experiment shows that HEA infl uences the disproportionation/ comproportionation equilibrium. Larger quantities of HEA lead to higher apparent rate constants and less disproportionation of CuBr which is in agreement with the supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) mechanism and not with the single electron transfer-living radical polymerization (SET-LRP) mechanism.to synthesize amphiphilic diblock [ 2 ] (AB) or triblock [ 3 ] (BAB) copolymers bearing cross-linkable moieties on the hydrophobic B-blocks. These block copolymers self-assembled in aqueous solution and formed star-like [ 2,4,5 ] or fl owerlike [ 3,6 ] polymeric micelles that could be rendered permanent by in situ photo-cross-linking.Reversible deactivation radical polymerization (RDRP) techniques have been shown to allow synthesis of PHEA in a controlled manner, both in the bulk and in solution. PHEA homopolymers are readily synthesized by nitroxide mediated polymerization (NMP), [ 7 ] reversible addition fragmentation chain transfer (RAFT), [ 8,9 ] atom transfer radical polymerization (ATRP), [ 10 ] and RDRP catalyzed by copper(0) associated to copper halides [ 11,12 ] (usually called

Aqueous SARA ATRP using inorganic sulfites

“…It provides access to a myriad of (co)polymers with precisely controlled architecture, including stars, brushes, and nanogels, as well as block, gradient, and statistical copolymers with specific functionalities. 9,16-20 Several variations of the normal ATRP method have been developed aiming to reduce the catalyst levels, such as: activators regenerated by electron transfer (ARGET) ATRP 21-24 ; initiator for continuous activator regeneration (ICAR) ATRP 25,26 ; supplemental activator and reducing agent (SARA) ATRP 27-34 ; electrochemically mediated ATRP (eATRP) 35-38 ; and photochemically mediated ATRP. 39-44 …”

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

“…The POEGA was selected due to its biocompatibility, low toxicity, and high hydrophilicity . PHEA additionally exhibits low thrombogenicity and cytotoxicity …”

“…[56][57][58] PHEA additionally exhibits low thrombogenicity and cytotoxicity. [59][60][61] This article presents a synthesis of the new ATRP macroinitiator based on the naturally derived substrate -vitamin B 2 and its application to prepare well-defined macromolecules, consisting of a riboflavin core and double hydrophilic PNIPAM-b-POEGA or PNIPAM-b-PHEA block copolymers with controlled MWDs through low ppm ATRP procedures. Additionally, preparation of hydrophobic poly(methyl methacrylate) (PMMA) and poly(n-butyl acrylate) (PBA)-based riboflavin-based macromolecules is reported (Figure 1 and Figure S3, Supporting Information).…”

Polymer Brushes via Surface-Initiated Electrochemically Mediated ATRP: Role of a Sacrificial Initiator in Polymerization of Acrylates on Silicon Substrates

“…In 2013, Percec et al polymerized HEA in situ in a protic solvent (methanol, MeOH; ethanol, EtOH; water, H 2 O) and a dipolar aprotic solvent (dimethyl sulfoxide, DMSO) with the Cu 0 wire-mediated ATRP technique (957 ppm of Cu) [52]. Further kinetic investigation of both the polymerization of HEA and copolymerization of HEA from a poly(ethylene oxide) initiator in DMSO and H 2 O showed higher monomer conversion for the aqueous process [53,54]. Nevertheless, both tested ligands introduced certain limitations.…”

“…Nevertheless, both tested ligands introduced certain limitations. Application of tris [2-(dimethylamino)ethyl]amine (Me 6 TREN) resulted in an extension of the induction time, whereas N,N,N',N",N"-pentamethyldiethylenetriamine (PMDETA) led to increased dispersity of the PHEA segment [54]. In another example, classical ATRP was used to graft PHEA chains via the grafting to approach (5 908 ppm of Cu).…”