A new photoiniferter/RAFT agent for ambient temperature rapid and well‐controlled radical polymerization

Abstract

Phenacyl morpholine-4-dithiocarbamate is synthesized and characterized. Its capability to act as both a photoiniferter and reversible addition fragmentation chain transfer agent for the polymerization of styrene is examined. Polymerization carried out in bulk under ultra violet irradiation at above 300 nm at room temperature shows controlled free radical polymerization characteristics up to 50% conversions and produces well-defined polymers with molecular weights close to those predicted from theory and relatively narrow poyldispersities (M w /M n $ 1.30). End group determination and block copolymerization with methyl acrylate suggest that morpholino dithiocarbamate groups were attained at the end of the polymer. Photolysis and polymerization studies revealed that polymerization proceeds via both reversible termination and RAFT mechanisms. V

Living Radical Polymerization by the RAFT Process - A Second Update

“…249 [408] MA [405] St [407] St [408] 250* [405] S S N N N S S 251 [404] MA [405] St [407,409] MA [405] St [404] 252* N N N S S 253 [283] S S N N St [409] 374 [410] MA/374 [410] St/374 [410] (NVCL) [384] N S S N N 255 [411] O S S N CN 256* MA [411] (St) [411] AA-b-NIPAM [412] 257 [283] S S N 258 [413] S S N O O St [413] (MA) [413] A See footnote A of Table 3. B See footnote B of Table 3.…”

“…[270,275,285,309,413,436] RAFT polymerization of St derivatives can be carried out at near ambient temperature (30 • C) with 115 as RAFT agent using 365 nm irradiation and (2,4,6-trimethylbenzoyl)-diphenylphosphine oxide as photoinitiator. [309] The same photoinitiator with 420 nm irradiation was used in ambient temperature RAFT polymerization of the UV sensitive cinnamate derivative 298 [436] and for polymerization of BA and MA under solar irradiation (>400 nm) at 20 • C. [270] The use of ionizing radiation to initiate RAFT polymerization has been reviewed.…”

Photoinitiated Polymerization: Advances, Challenges, and Opportunities

“…Although with limited success, there have been a number of attempts to extend such control to polymerizations conducted photochemically. 232 The earlier approach based on reversible combination of growing radicals with a scavenging radical was applied in thermal and photoinitiated radical polymerization. According to Otsu,233 photochemical polymerization of vinyl monomers with dithiocarbamates, referred to as iniferter (initiator-transfer-terminator), 234 is characterized by the initial rapid growth and an increase in molecular weight with conversion (Scheme 26).…”

Controlled Photoradical Polymerization Mediated by 2,2,6,6-Tetramethylpiperidine-1-Oxyl

“…For the purpose of establishing controlled photoradical polymerization to well-control the molecular weight, new photoinitiators have been prepared; the dithiocarbamate derivatives [52,53], trithiocarbonate [54,55], dithiodiethanol [56], xanthate [57], and a benzophenone derivative [58]. The potential of photopolymerization has also been explored for thermal RAFT and ATRP polymerizations using photosensitive initiators [59][60][61][62] and a catalyst containing dithiocarbamate [63]. More recently, it was found that TEMPO-mediated controlled/living photoradical polymerization provided comparatively narrow molecular weight distribution (MWD) for methyl methacrylate (MMA) [36,37,41,43].…”