Reversible deactivation radical polymerization

All CRP methods rely on a dynamic equihbration between tiny amounts of propagating radicals and various types of dormant species. The essence of the process is a rapid reversible deactivation of growing radicals. Radicals always terminate and therefore CRP is never living in the pure sense of the living polymerization definition. Indeed, lUPAC recommends to avoid using term Uving for the radical polymerization and suggests to use the term controlled reversible deactivation radical polymerization . 

Jenkins, A.D., Jones, R.G., Moad, G., 2010. Terminology for reversible-deactivation radical polymerization previously called controlled radical or living radical polymerization. Pure Appl. Chem. 82 (2), 483 91. 

As of 1990, this conventional free radical polymerization is developed to the newer reversible deactivation radical polymerization. More details of each will be... 

Glossary of terms relating to kinetics, thermodynamics, and mechanisms of polymerization. The document represents, in alphabetical order, recommended definitions of terms related to polymerization processes, principally to kinetics, thermodynamics, and mechanisms of polymerization. Since polymerization processes have specific features, the definitions presented in this document differ in some instances from the general definitions given in the Gold Book. The document on reversible deactivation radical polymerization is a logical extension of this glossary. 

Terminology for reversible-deactivation radical polymerization previously called controlled radical or living radical polymerization Pure Appl. Chem. 82 (2010) 483. 

ATRP is one of the methods in reversible-deactivation radical polymerization that produces well-defined vinyl polymers [86-88]. The mechanism of ATRP is shown... 

Reversible addition-fragmentation chain transfer polymerization is a reversible deactivation radical polymerization and it represents one of the most versatile methods for providing living characteristics to radical polymerization and polymers of predictable chain length and narrow molecular weight distribution. 

Reversible deactivated radical polymerization processes, which have been referred to as living/controlled radical polymerizations, allow for producing polymeric materials with controlled molecular masses, low dispersities, and complex maaomolecular architectures, such as block and comb-like copolymers as well as star-shaped (co)polymers. In addition to nitroxide-mediated polymerization (NMP) ° and atom-transfer radical polymerization (ATRP), ° reversible addition fragmentation chain-transfer (RAFT) polymerization is an attractive new method. " ... 

The beneficial action of high pressure on reversible deactivated radical polymerization is not restricted to RAFT systems... 

For this section we use the lUPAC recommended term reversible deactivation radical polymerization (RDRP). Termination is present in all of the polymerizations described, even though many polymerizations display many of the observable characteristics normally associated with living polymerization. 

Scheme 5 General scheme of reversible-deactivation radical polymerization.

Another limitation of ITP is that the rate of exchange between dormant and active chains is rather slow in comparison with other reversible-deactivation radical polymerization methods (for instance, Cex= 3.6 for ITP of styrene, whereas Cex= 180 for RAFT of styrene at 80 According to eqn [21], it implies that the PDI of polymers obtained by ITP is rather high (it is actually typically in the range of 1.2-1.6 for PS, 1.2-1.6 for poly(MMA), and 1.7-2.1 for poly(butyl acrylate) obtained by RITP in bulk at 80 °C). To address this limitation, Goto et proposed a new technique of polymerization called... 

It must be noted here that, contrary to the general belief, FTP is not the only reversible-deactivation radical polymerization method to control the polymerization of fluotinated olefins. Indeed, it has been shown that poly(VDF-co-HFP) could be obtained with a good control of molecular weight by RAFT with a-(0-ethylxanthyl)methyl propionate as control... 

Other language has been used to describe this process. Indeed many authors have intermittently used other names/abbrevia-tions for reactions utilizing the same components to clarify specific aspects of the reaction. " This multiplicity of nomenclature may have aeated confusion as to the fundamental similarity, or indeed identical nature of the reactions being discussed. A recent recommendation by lUPAC clarifies this position by recommending that specific reversible-deactivation radical polymerizations (RDRPs) should adopt terminology consistent with that in lUPAC documents, specifically that the controlled RDRP procedures in which the deactivation of the radicals involves catalyzed reversible atom transfer or reversible group transfer usually, though not exclusively, by transition metal complexes be named atom transfer radical polymerization, ATRP. °... 

Konkolewicz D, Wang Y, Zhong M, Krys P, Isse AA, Gennaro A, Matyjaszewski K (2013) Reversible-deactivation radical polymerization in the presence of metallic copper. 

Keywords Nanoparticles Phase separation Polymeric architecture Reversible-deactivation radical polymerization Self-assembly... 

Controlled radical polymerizations (also called reversible-deactivation radical polymerization, RDRP, according to lUPAC recommendations) offer a unique way to modulate polymeric materials at the molecular level. By exploiting a dormant state of the propagating macroradical, the fraction of irreversibly terminated species... 

Wang, Y, Zhong, M., Zhu, W., Peng, C.-H., Zhang, Y., Konkolewicz, D., Bortolamei, N., Isse, A.A., Gennaro, A., Matyjaszewski, K. Reversible-deactivation radical polymerization in the presence of metallic copper. Comproportionation-disproportionation equilibria and kinetics. Macromolecules 46(10), 3793-3802 (2013)... 

Several controlled and living radical polymerization techniques are available today. All are based on the reversible deactivation of growing chains. Consequently, a 2010 lUPAC recommendation proposes the term controlled reversible-deactivation radical polymerization (CRDRP) for polymerizations previously referred to as controlled radical (CRP) or living radical (LRP) polymerization. Nevertheless, due to their widespread acceptance, the terms controlled/living radical polymerization will also be used in this chapter. 

Polymerization with reversible addition-fragmentation chain transfer (RAFT) is a reversible deactivation radical polymerization (RDRP) a process which, with appropriate attention to reagents and reaction conditions, can possess the attributes usually associated with living polymerization. These processes are also often called hving radical polymerizations or controlled radical polymerizations. However, the use of these terms in this context is now discouraged. ... 

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