The Photolysis of Dithiocarbamates and their Catalytic Effects on Photopolymerization

Iniferter concept and living radical polymerization

“…Another disadvantage is that, for example, polymer 5 produced from 1 of the C–C type is unfavorable for preparing the controlled block copolymers because two dithiocarbamate end groups are bonded to the different carbon atoms of the terminal monomer untis to form the α and ω ends, as is rewritten by 15 . That is, the CS bond, shown by an arrow, at the ω end would be more easily dissociated photochemically than that at the α end, as was pointed out by Okawara et al:32 where the structures of the α and ω end groups bonded to the terminal monomer units correspond to those of 2‐phenethyl N,N ‐diethyldithiocarbamate ( 16 ) and benzyl N,N ‐diethyldithiocarbamate ( 18 ) , respectively, as A–B‐type model compounds. Therefore, radical dissociation in 15 , 16 , and 18 occurs at different bonds, as shown by the arrows in eqs 12 and 13: where 16 acts as a weaker photoinitiator than 18 , which serves as an excellent photoiniferter because a benzyl radical similar to the propagating radical of St is produced 25.…”

Resistance of zwitterionic telomers accumulated on metal surfaces against nonspecific adsorption of proteins

“…Of various procedures for pursuing controlled radical polymerization, the use of an iniferter (a compound that pursues initiation, chain transfer, and termination) has received much attention due to its ease [47][48][49][50][51][52][53][54][55][56]. Of the iniferters used, N ,N -diethyldithiocarbamoyl derivatives have been most extensively studied [47][48][49][50][51][53][54][55][56].…”

Mechanism of the polymerization ofn-butyl acrylate initiated byN,N-diethyldithiocarbamate derivatives. Part 2. Investigation of the reaction mechanism

“…It has been shown by Okawara et al 15 that the photodecomposition of wCH 2 wCH 2 wSwC(S)NEt 2 groups occurred preferentially between S and C(S) (rather than between and S for the "normalÏ end-CH 2 groups leading to reversible termination). The two radicals and may initiate new wCH 2 wCH 2 wS~Et 2 NC~(S) chains, but progressively the thiocarbamyl end-groups will be replaced by non-reactive wCHXwC(S)wNEt 2 end-groups.…”