Controlled/living cationic polymerization of styrene with BF3OEt2 as a coinitiator in the presence of water: Improvements and limitations

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“…Besides, the polymerization of styrene or p ‐(chloromethyl)styrene, investigated only at rather low water content, was less controlled: the M n was close to the calculated value only at the later stage of polymerization and the obtained polymers exhibited broad MWDs ( M w / M n = 1.8–3.0) 17, 18. Moreover, we showed recently that R ‐OH/BF 3 ·OEt 2 initiating system indeed controls the styrene polymerization, but it is very sensitive to small changes in water contents and cannot be applied in aqueous dispersion due to the coinitiator decomposition 20. Quite recently, we reported a new initiating system, 1‐(4‐methoxyphenyl)ethanol ( 1 )/B(C 6 F 5 ) 3 , which polymerized p ‐methoxystyrene in a living fashion not only in the presence of excess of water to Lewis acid,21, 22 but also for the first time in aqueous dispersion 22.…”

Cationic polymerization of p-methylstyrene in selected ionic liquids and polymerization mechanism

“…The spectrum was characteristic of poly( p-MeSt) with resonances because of phenyl groups (d), main-chain aliphatic protons (b and c), and -CH 3 protons attached to the aromatic ring (e). 75 Fig. They were CH 3 -(α; 1.0 ppm) at the α-end resulting from the initiator fragment (CumOH), the methoxy terminal group (ω; 2.9-3.0 ppm) at the ω-end resulting from the quenching of the polymerization with methanol, 67,68 and the terminal -CH proton (f; 4.1-4.3 ppm) attached to the -OCH 3 and -OH (formed due to the reversible termination reaction) groups.…”

Novel acid initiators for the rapid cationic polymerization of styrene in room temperature ionic liquids

“…There have been recent reports, involving different Lewis acids, salts and solvents to stabilize the carbocation, to reduce side reactions and produce living polymers [6,7]. Studies pertaining to controlled polymerization of vinyl monomers at different temperatures in conventional solvents have also been investigated [8][9][10]. However, the handling and disposal of the conventional Lewis acid initiators and the chlorinated solvents used remains an issue [11,12].…”