synonym: RAFT polymerization
initialism: RAFT
https://doi.org/10.1351/goldbook.08935
Degenerate-transfer radical polymerization in which chain activation and chain deactivation involve a degenerative chain-transfer process, which occurs by a two-step addition-fragmentation mechanism.
Notes:
- The term RAFT polymerization (unqualified) usually refers to polymerization mediated by a carbonothioylsulfanyl RAFT agent.
- There are various forms of RAFT polymerization that differ in details of the initiation mechanism, the reaction conditions and/or the reagents used. These include:
- Carbonothioylsulfanyl RAFT polymerization. The more commonly used term thiocarbonylthio RAFT polymerization is deprecated as it is inconsistent with IUPAC nomenclature. Examples of carbonothioylsulfanyl RAFT agents include certain dithioesters, trithiocarbonates, xanthates (dithiocarbonates), and dithiocarbamates with structure \(\ce{S=C(Z)-SR}\), where \(\ce{Z}\) is aryl, alkylsulfanyl, alkyloxy, or dialkylamino, respectively, and \(\ce{R}\) is a homolytic leaving group.
- Macromonomer RAFT polymerization where the RAFT agent is a 'macromonomer' with structure \(\ce{CH2=C(Z)-CH2R}\), where \(\ce{Z}\) is usually \(\ce{-CO2alkyl}\) or \(\ce{-CO2aryl}\) and \(\ce{R}\) is a homolytic leaving group. This form of RAFT polymerization is also known as sulfur-free RAFT polymerization.
- MADIX (macromolecular design by interchange of xanthate) where the RAFT agent is a xanthate.
- PhotoRAFT polymerization where radical generation involves direct photolysis of a carbonothioylsulfanyl-RAFT agent to give an initiating species and a carbonothioylsulfanyl radical.
- PET-RAFT (photo-induced energy or photo-electron-transfer RAFT) polymerization where radical generation involves photo-induced energy or electron transfer from a photoredox catalyst or a photosensitizer, respectively, to a carbonothioylsulfanyl-RAFT agent which then dissociates to give an initiating species.
- redoxRAFT where radical generation involves ISET or OSET between the RAFT agent and a reducing agent agent to give an initiating species.
- eRAFT polymerization where radical generation involves electrochemical reduction of the RAFT agent either directly or through a redox mediator.