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6594261 
Journal Article 
Macromolecular design via the interchange of xanthates (MADIX): Polymerization of styrene with O-ethyl xanthates as controlling agents 
Destarac, M; Brochon, C; Catala, JM; Wilczewska, A; Zard, SZ; , 
2002 
1 
Macromolecular Chemistry and Physics
ISSN: 1022-1352 
WILEY-V C H VERLAG GMBH 
WEINHEIM 
203 
16 
2281-2289 
English 
WOS:000180766600003 
Control of the free-radical polymerization of styrene was achieved using a series of eight xanthates of the general structure R-A(C=A)OEt as reversible addition fragmentation chain-transfer agents. The influence of the nature of the R leaving group was explored. It was found that the transfer ability of the xanthate is markedly improved with increasing stability of R and its steric hindrance. Group R strongly influences the M-n evolution profile during polymerization, but only influences the polydispersities to a small extent. The cyanoisopropyl group was shown to be the best leaving group, leading to an increase in the molecular weight during polymerization that was close to linearity. The living character of the polymerization and the high purity of the chain structures were supported by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and C-13 NMR spectroscopy. A zero-order dependence of the kinetics of polymerization on the xanthate concentration was observed. 
MADIX; MALDI; Molecular weight distribution; Radical polymerization; Xanthates