Thiocarbonylthio RAFT

Figure 93 General description of macromonomer and thiocarbonylthio RAFT...

Living radical polymerization using thiocarbonylthio RAFT agents (including dithioesters, trithiocarbonates and xanthates) was first described in a patent published in 1998.40S The first paper describing the process also appeared in 1998.1R Other patents and papers soon followed. Papers on this method, along with NMP and ATRP, now dominate the literature on radical polymerization. 

Many thiocarbonylthio RAFT agents (164) have now been described. Transfer constants are strongly dependent on the Z and R substituents. For an efficient RAFT polymerization (refer Scheme 9.38 and Figure 9.3) ... 

A wide variety of thiocarbonylthio RAFT agents (ZC(=S)SR, 1) have now been reported. A broad summary of these and the factors which influence choice of RAFT agent for a particular polymerization is presented in recent reviews.The effectiveness of the RAFT agent depends on the monomer being polymerized and is determined by the properties of the free radical leaving group R and the group Z which can be chosen to activate or deactivate the thiocarbonyl double bond of the... 

Thiocarbonylthio RAFT agents include certain dithioesters, trithiocarbonates, xanthates, dithiocarbamates, and other compounds. Figure 5 provides general guidance on how to select the appropriate thiocarbonylthio RAFT agent for a particular monomer. It should be dear that with just two RAFT agents it should be possible to exert effective control over the vast... 

RAFT Polymerization with Thiocarbonylthio RAFT Agents... 

The chain activation-deactivation mechanism in thiocarbonylthio RAFT polymerization (Scheme 6.7) is directly analogous to that in macromonomer RAFT polymerization (Scheme 4.4). However, rate constants for radical addition to the thiocarbonylthio double bond are typically several orders of magnitude higher than those to analogous carbon arbon double bonds and... 

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