Reversible addition-fragmentation thiocarbonylthio compounds

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]

Chong, Y.K., Krstina, J., Le, T.P.T., et al., 2003. Thiocarbonylthio compounds [Sc(Ph)S-R] in free radical polymerization with reversible addition-fragmentation chain transfer (RAFT polymerization). Role of the free-radical leaving group (R). Macromolecules 36 (7), 2256-2272. 

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... 

Control of radical poljmerization with the addition of thiocarbonylthio compounds that serve as reversible addition fragmentation chain transfer (RAFT) agents was first reported in 1998. Since that time much research carried out in these laboratories and elsewhere has demonstrated that RAFT polymerization is an extremely versatile process.f It can be applied to form narrow polydispersity poljmers or copolymers from most monomers amenable to radical poljmerization. It is possible to take RAFT poljmerizations to high conversion and achieve commercially acceptable polymerization rates. Polymerizations can be successfully carried out in heterogeneous media (emulsion, miniemulsion, suspen-... 

Reversible Addition-Fragmentation Chain Transfer. The RAFT represents a process for performing living free radical polymerization. Many simple organic compounds possessing a thiocarbonylthio (S=C—S) moiety are employed... 

In some cases the product of chain transfer (P T) is itself a transfer agent and chain transfer is reversible. Examples include alkyl iodides (Scheme 6.4) and certain addition-fragmentation transfer agents (e.g. inacromonomers and thiocarbonylthio compounds) (Scheme 6.5). 

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