Acid dissolution of copper oxides as a method for the activation of Cu(0) wire catalyst for SET‐LRP

Abstract

Here we reported the acid dissolution of copper oxides as a methodology for the activation of Cu(0) wire used as catalyst in single‐electron transfer living radical polymerization (SET‐LRP). In this method, the oxide layer on the surface of commercial Cu(0) wire was removed by dissolution in a concentrated acid such as nitric acid, glacial acetic acid and hydrochloric acid. SET‐LRP of methyl acrylate catalyzed with Cu(0) wire activated with acids showed comparable k pitalicapp value to that of the nonactivated Cu(0) wire‐catalyzed counterpart. However, the polymerizations catalyzed with activated Cu(0) wire proceeded with no initial induction period, predictable molecular weight evolution with conversion, and narrow molecular weight distribution. Regardless of the activation method, the chain end functionality of α,ω‐di(bromo) poly(methyl acrylate) (PMA) prepared from SET‐LRP initiated with a bifunctional initiator is extremely high, maintaining a 100% chain end functionality at ∼90% monomer conversion. The degree of bimolecular termination increased as the polymerization exceeds 92% conversion. However, for binfunctional initiators this small amount of bimolecular termination at high conversion maintains a perfectly bifunctional polymer. Structural analysis by MALDI‐TOF upon thioetherification of α,ω‐di(bromo) PMA with thiophenol and 4‐fluorothiophenol confirmed the high fidelity of bromide chain ends. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

Aqueous SET-LRP catalyzed with “in situ” generated Cu(0) demonstrates surface mediated activation and bimolecular termination

“…10 42 exhibit amplified adsorption and desorption processes that may complement the previous studies on the elucidation of the role of the surface of Cu(0) catalyst on the activation and deactivation steps of SET-LRP. 11,[58][59][60][61] This publication reports the aqueous SET-LRP of HEA and OEOMEA mediated by "in situ" generated Cu(0) catalyst. 26,37,38 The study reported here demonstrates that the surface of Cu(0) is responsible both for the activation of the initiator and dormant growing species, as well as for the much lower extent of bimolecular termination observed during polymer synthesis by SET-LRP.…”

“…56 Most monomers used in SET-LRP can often mediate this disproportionation but do not always dissolve Cu(II)X 2 limiting its usefulness under certain conditions. 10,46,57 The catalyst most frequently employed in SET-LRP is Cu(0) in the form of powder 2,4,12,58 including powder generated by the disproportionation of Cu(I)X in a large diversity of solvents, 12 wire, 12,64,69 activated wire [59][60][61][62] and tubes. 63,64 Almost all initiators employed in other metal catalyzed LRP such as alkyl halides, 65,66 sulfonyl halides, 33,48,65,[67][68][69] N-halides 2,70 can be used as such or modified to become soluble for SET-LRP in various media including H 2 O.…”

Copolymerization of styrene and methyl methacrylate mediated by iron wire/N,N,N′,N′-tetramethyl-1,2-ethanediamine as catalyst in the presence of air

“…However, normal ATRP has some limits, such as water-and oxygen-free systems. Therefore, some improved ATRP techniques have been developed, for example, reverse ATRP (RATRP) [3,4], initiators for continuous activator regenerated by electron transfer ATRP (ICAR ATRP) [5,6], simultaneous reverse and normal initiation (SRNI ATRP) [7], activators generated by electron transfer ATRP (AGET ATRP) [8,9], activators regenerated by electron transfer ATRP (ARGET ATRP) [10,11] and single electron transfer-living radical polymerization (SET LRP) [12][13][14]. SET LRP was first investigated by Percec et al [15].…”

Single electron transfer-living radical polymerization of acrylonitrile catalyzed by lanthanum powder

“…[28][29][30][31] To establish the proper equilibrium between active and inactive chains, suitable solvents and ligands that enhance the disproportionation of Cu(I) complexes must be used. For this purpose, solvents like dimethyl sulfoxide (DMSO), 32,33 trifluoroethanol, 34 alcohol, [35][36][37] water, [38][39][40][41][42] ionic liquid, 43,44 and the combination of organic solvent mixture, 45,46 and ligands such as tris(2-(dimethylamino)ethyl)amine, 47,48 tris(2-aminoethyl)amine, 49-51 and polyetherimide 52 have been successfully applied. Effects of ligand on the apparent rate constant of propagation of SET-LRP of methyl acrylate (MA) in DMSO have been reported.…”

“…However, it has been accomplished only for activated monomers. [18][19][20][21][22][23] The defective has been perfected by SET-LRP for its polymerization of nonactivated vinyl chloride. [24][25][26] From the mechanism of SET-LRP, activation of initiator and dormant halide chain ends is catalyzed by the out-sphere electron transfer (OSET).…”