Synthesis of sequence‐controlled copolymers from extremely polar and apolar monomers by living radical polymerization and their phase‐separated structures

Abstract

A series of copolymers composed of two monomer units having a polar phosphorylcholine group and an apolar fluorocarbon group with a controlled monomer unit sequence were synthesized by a reversible addition‐fragmentation chain transfer (RAFT) living radical polymerization method. 2‐Methacryloyloxyethyl phosphorylcholine (MPC) and 2,2,2‐trifluoroethyl methacrylate (TFEMA) were selected as the monomers, because they have disparate polarity. Furthermore, to investigate the influence of the monomer unit sequence in a polymer chain on the phase‐separated structure in the bulk and surface structure, copolymers having a continuous change in the monomer unit composition along the polymer chain (gradient copolymer) were synthesized, as well as random and block copolymers. The analysis of instantaneous composition revealed a continuous change in the monomer unit composition in the gradient copolymer and the statistical monomer unit sequence in the random copolymer. Thermal analysis assumed that the gradient sequence of the monomer unit would make the phase‐separated structure in the bulk ambiguous, while the well‐defined and monodispersive block sequence would undergo the distinct phase‐separation due to the extreme difference in the polarity of the component monomer units. The preliminary surface characterization of the synthesized polymers indicated the monomer unit sequence in the polymer chain would much influence on the surface structure. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6073–6083, 2005

Experimental Requirements for an Efficient Control of Free‐Radical Polymerizations via the Reversible Addition‐Fragmentation Chain Transfer (RAFT) Process

“…. [125] EtOEA [264] -C(Me)(CN)CH 2 CH(Me) 2 MMA [124] -C(Me)(CN)CH 2 CH 2 CO 2 H MAA a) [109] MMA [67,339] a) [109,143] b) [208] tBMA [153] DMAEMA [72,110,145,166] MAPS [160] DMAPS [169] c) [170] MAEHDMAB a) [143] MEPC [149,156] TFEMA [156] GluMA [172,173] MGluMA [173,174] Macro-MA a) [109] PEG-MA [100,160] MAm [178] DMAPMAm [179] HPMAm [180] MSASP [160] Sty [67,153,208] StySO 3 Na [67,72,110,235,236] StyCH 2 NH-(Me) 2 Cl [239] StyCH 2 N(Me) 3 Cl [235,236,239] DMHVBAC a) [143] DMVBAPS [169] BA a) …”

Amphiphilic gradient copolymer of [poly(ethylene glycol) methyl ether] methacrylate and styrene via atom transfer radical polymerization

“…Gradient copolymers are of great interest because of their fascinating properties [1][2][3][4][5][6][7][8][9][10][11][12][13][14] and their simple synthesis via controlled/living radical polymerization (CRP) techniques, 15 such as atom-transfer radical polymerization (ATRP), 2,[16][17][18][19] reversible addition-fragmentation transfer (RAFT), 20,21 and nitroxide-mediated CRP. 4,6,[8][9][10][11][12][13][22][23][24] Gradient copolymers have also been synthesized using other living or pseudo-living polymerization methods such as ring-opening metathesis polymerization 7,14,25 and cationic polymerization.…”

Bonding durability against water of a fluorine-containing resin for precious metal alloys

“…Therefore, the abnormally high water sorption of the fluorinated resin was probably due to the initiator, TBBO. It has been reported that the block copolymer of TFEMA with a hydrophilic monomer exhibits a phase-separated structure because of the extreme difference in their polarity 27) . In TFEMA-PTFEMA/TBBO resin, the concentration of TBBO in the TFEMA monomer liquid was relatively high, 8 wt%, and TBBO is known to exhibit a hydrophilic nature in polymerization reactions 28) .…”