Kinetics of methyl, ethyl, and isopropyl vinyl ether polymerizations initiated by trityl salts

A benign initiating system for cationic polymerization of isobutyl vinyl ether: Silver salt/aryl(alkyl) halide/lewis base

“…At −23 °C, polymerization via Addition Order I produced the best result (Entry 5), in contrast with the very low conversion obtained using Addition Order II (Entry 6). On the other hand, the more stable and bulky triphenylmethyl cation appears to be relatively unaffected by the addition order (Entries 7 and 8), that is by Me 2 S, at −23 °C …”

“…In order to establish the best system for use, we evaluate herein the effects of the type of added base, order of addition of the reagents, and types of silver salts on the polymerization reaction. Isobutyl vinyl ether (IBVE) is selected as one of the VE monomers, and is known to be an active monomer for cationic polymerization . The versatile polymers, poly(VE)s, may be used in various applications by exploiting their high polarizability and the flexibility of their side chains …”

“…Isobutyl vinyl ether (IBVE) is selected as one of the VE monomers, and is known to be an active monomer for cationic polymerization. [21][22][23] The versatile polymers, poly(VE)s, may be used in various applications by exploiting their high polarizability and the flexibility of their side chains. 1,[24][25][26][27]…”

Cationic polymerization of alkenes and heterocyclics. More similarities than differences

“…Polymerization is negative first order in deactivator and using large excess of deactivator one can assume that the concentration of initiator is equal to that of onium ions. Thus, the apparent rate constant of propagation equals the ratio of true propagation rate constant (kp+) 46 and the product of equilibrium constant between carbenium and onium ions times concentration of deactivator:…”

“…The latter were determined by the dynamic NMR method for the isobutyl vinyl etherhetrahydrothiophene systemfl. Using values of the rate constants of propagation 46 and the deactivation rate constants deduced from the NMR method, one gets very low polydispersities, nearly of the Poisson type. Thus, any broadening of the polydispersities in these systems have to originate not in the exchange reactions but in slow initiation, inefficient mixing, and transfer or termination.…”