MADIX polymerization

We thus speculate that polyacrylamide growing chains have a reduced accessibility to the terminal xanthate moiety. As a matter of fact, a mixture of XG-6-PAm diblock shghtly contaminated by residual XG-CTA is obtained after MADIX polymerization. Almost complete elimination of the residual XG-CTA could be achieved, however, by dialysis against water, as illustrated in Figure 5. 

Polymerization of VPA was successfully performed by aqueous RAFT/ MADIX polymerization, controlled with O-ethyl xanthate as a transfer agent. Reversible addition-fragmentation chain transfer (RAFT) is a polymerization method which uses a chain transfer agent in the form of a thiocarbonylthio compound such as dithioesters, thiocarbamates, and xanthates having the role to mediate the polymerization via a reversible... 

Scheme 4.15 RAFT/MADIX polymerization of vinylphosphonic acid.

Perrier, S. and Pittaya, T. (2005) Macromolecular design via reversible addition-fragmentation chain transfer (RAFT)/xanthates (MADIX) polymerization.. Polym. Sci., Part A Polym. Chem., 43, 5347-5393. 

Although the term RAFT (an acronym for Reversible Addition-Fragmentation chain Transfer)38" is sometimes used in a more general sense, it was coined to describe, and is most closely associated with, the reaction when it involves thiocarbonylthio compounds. RAFT polymerization, involving the use of xanthates, is also sometimes called MADIX (Macromolccular Design by Interchange of Xambate) 96 The process has been reviewed by Rizzardo et [Pg.502]

MADIX)/RAFr polymerization of vinyl acetate was earned out to grow poly(vinyl acetate) chains from the initiating sites of the as-prepared polyinitiator backbone. The resulting poly (vinyl acetate) side chains were hydrolyzed to yield water-soluble poly(vinyl alcohol) molecular bmshes. 

Destarac, M., et al. 2002. Xanthates as chain-transfer agents in controlled radical polymerization (MADIX) structural effect of the O-alkyl group. Macromolecidar Rcpid... 

Polymerization of vinyl acetate monomer can be effected by bulk, solution, or emulsion techniques. The poly(vinyl acetate) formed is then dissolved in solvent (eg, CH3OH) and alcoholized/hydrolyzed with acidic or basic catalysts. Vinyl acetate can also be polymerized in a controlled fashion via RAFT/MADIX (115). PVA is insoluble in CH3OH and precipitates. It is isolated by filtration, washing, and drying. 

Control by degenerative transfer (DT) involves perhaps the smallest change from a eonventional free radical process of all the controlled/living polymerization proeesses developed to date. A recent review of various methods of telomer synthesis [180] diseusses the different types of transfer agents and monomers and the contribution of the teehniques of telomerization to CRP (includes discussion of iodine transfer polymerization, RAFT, and macromolecular design through interchange of xanthates (MADIX)) [181,182]. 

Figure 3 (a) Cumulative citations for our first communication on RAF (A), our first patent and our 2005 (°) review on RAF polymerization and that published in Polymer in 2008 (0). Based on SciFindet search carried out in February 2011.(b) Total publications, papers, and patents on RAF polymerization based on SciFinder search of terms RAF polymerization , reversible addition-fragmentation transfer and radical , and MADIX and radical . The term papers includes journal, articles, communications, letters, and reviews but does not include conference abstracts. 

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