Aqueous copper(0) mediated reversible deactivation radical polymerization of 2-hydroxyethyl acrylate

Abstract

a Reversible deactivation radical polymerization (RDRP) of 2-hydroxyethyl acrylate in D2O with Cu(0) wire mediation and with two-step Cu(0) in situ mediation was investigated. The concentration of active species on the Cu(0) surface, which was influenced by Cu(0) type (wire or particle), polymer chain length, and activator and deactivator concentration, was the key factor in understanding the formation of insoluble gel with Cu(0) wire and/or a high molecular weight (MW) shoulder observed in the polymer molar mass distributions (MMDs). The influences of temperature, residual oxygen (dependent on the transfer procedure used to add reagents), and NaBr addition were also studied. The insights gained were used to produce P(HEA) with high molar mass [target chain length (TCL) =400, 87% conversion, Đ=1.16] using only ca. 250 ppm copper at room temperature, the first reported preparation of high MW P(HEA) with a low Đ using such a low copper catalyst concentration in a purely aqueous environment.

Methacrylic Zwitterionic, Thermoresponsive, and Hydrophilic (Co)Polymers via Cu(0)-Polymerization: The Importance of Halide Salt Additives

“…It is important to stress that a chloride salt was preferred to a bromide salt to avoid unsatisfactory halogen‐exchange throughout polymerization . Although the quantity of salt present in the reaction medium is greater than in previous reports, the speed of the polymerization was not affected (as opposed to previous investigations), as full monomer conversions could still be attained within 30 min. In order to probe the potential of the technique to afford good control to both lower and higher molecular weights (co)polymers, a range of targeted DP n s were attempted ( DP n = 10–160, Table ).…”

“…The large dispersity value indicates that termination events remain prevalent in the halogen exchange system, which can be attributed to inefficient deactivation due to dissociation of the deactivating complex ([Cu II (PMDETA)Cl]Cl) . It had been suggested that the addition of external halide salts can improve the control over the polymerization, by reducing the extent of complex dissociation, as previously reported . Hence the polymerization of PEGMA 475 ([I]:[M]:[PMDETA]:[CuCl]= 1:40:0.6:1.1, 20% v/v monomer in water) was conducted with an external halide source (NaCl,) utilizing previously reported concentrations (0.3 m ) .…”

“…Nevertheless, a significant loss of the halide chain ends at high monomer conversion, detrimental for the synthesis of functional block copolymers, associated with an increase in the molecular weight distributions (MWDs) would still be observed. Interestingly, the introduction of a supplementary halide source (e.g., TEABr, NaCl, NaBr salts) is reported to enhance the retention of the halide chain end(s) at moderate conversion and would narrow the molecular weight distribution (MWD) as low as Đ ≈ 1.3 for poly[poly(ethylene glycol) methyl ether methacrylate] (PEGMA 475 ) …”

Recent Developments in the Synthesis of Biomacromolecules and their Conjugates by Single Electron Transfer–Living Radical Polymerization

“…Monomers such as 2-ethylhexyl acrylate (EHA), ,,, benzyl acrylate (BzA), and 2-methoxyethyl acrylate (MEA) , have successfully produced the corresponding polyacrylate under SET-LRP conditions. The list is so broad that it ranges from hydrophobic such as adamantly acrylate (ADA), lauryl acrylate (LA), and octadecyl acrylate (OA) to hydrophilic and water-soluble acrylates such as 2-hydroxyethyl acrylate (HEA), ,− ,, 2-acryloyloxyethyl phosphorylchlorine (APC), di­(ethylene glycol) 2-ethylhexyl ether acrylate (DEGEEA), and oligo­(ethylene oxide) methyl ether acrylate (OEGMEA). ,,− Monomers such as solketal acrylate ((2,2-dimethyl-1,3-dioxolan-4-yl)­methyl acrylate) (SA), glycidyl acrylate (GA), o -nitrobenzyl acrylate (NBA), dithiophenolmaleimide acrylate (DMMA), acrylic acid 3-trimethylsilanyl-prop-2-ynyl ester (TMSPA), N , N -dimethylaminoethyl acrylate (DMAEA), pentaerythritol triacrylate (PETA), and 2-(acryloyloxy)­ethyl 3,4-bis­(2-phenylethynyl)­benzoate (ABPB) have been polymerized by SET-LRP leading to functionalized polymers. Our laboratory also reported the polymerization of several semifluorinated acrylates such as 1 H ,1 H ,2 H ,2 H -perfluorooctyl acrylate (PFOA), 2,2,3,3,4,4,4-heptafluorobutyl acrylate (HFBA), 1,1,1,3,3,3-hexafluoroisopropyl acrylate (HFIPA), and 1 H ,1 H ,5 H -octafluoropentyl acrylate (OFPA), whereas others reported that SET-LRP is also compatible with sugar-containing acrylates such as glucose acrylate (GlcA), mannose acrylate (ManA), − fucose acrylate (FucA), and 2-[( d -glycosamin-2- N -yl)­carbonil]­oxyethyl acrylate (HEAGI) …”

Iron-Mediated Homogeneous ICAR ATRP of Methyl Methacrylate under ppm Level Organometallic Catalyst Iron(III) Acetylacetonate

“…Reversible deactivation radical polymerization (RDRP) [1,2,3,4,5,6,7] including initiator-transfer agent-terminator (Iniferter) [8,9,10,11], nitroxide-mediated polymerization (NMP) [12,13,14,15,16,17,18], atom transfer radical polymerization (ATRP) or metal-catalyzed living radical polymerization [19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43] and reversible addition−fragmentation chain transfer polymerization (RAFT) [44,45,46,47,48,49,50,51,52,53,54,55] has been used to design and synthesize various polymeric structure and architectures extensively. Among those methods, ATRP is the most widely used method and has been used to produce different topological polymers, such as star, brush, block and hyperbranched polymers [56,57,58,59].…”