Organotellurium-mediated living radical polymerization (TERP) of n-butyl acrylate (BA) in emulsifier-free emulsion polymerization system was carried out for the first time, using the in situ nucleation technique via self-assembly of the propagating amphiphilic polymer chains derived from water-soluble TERP agent, poly(methacrylic acid)-methyltellanyl, with water-soluble thermal initiator, 4,4′-azobis(4-cyanovaleric acid), as a radical source at 60 °C. The polymerization proceeded with high control/livingness to high conversion without coagulation, resulting in nanosized poly(BA) particles. The difference in the stirring rates of the polymerization system, where the whole monomer dispersed as droplets at a high rate or it existed as an upper layer on the aqueous medium at a low rate, had a great influence both on the rate of polymerization and on the degree of the control/livingness. On both of them, the polymerization with the high stirring rate gave more desirable results than those with the low rate. † Part CCCXXII of the series "Studies on Suspension and Emulsion".

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Modeling and simulations of compartmentalization effects in tandem with nitroxide exit and entry have been performed for the nitroxide-mediated radical polymerization (NMP) of styrene in an aqueous dispersed system employing 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) at 125 °C. It is demonstrated that, even for a relatively water-insoluble nitroxide like TEMPO, exit and entry can strongly influence the polymerization kinetics in submicrometer-size droplets/particles. In such systems, the polymerization is expected to proceed at a markedly higher rate than the corresponding bulk system at the expense of control/livingness. Depending on the deactivator water solubility, these findings will apply qualitatively to all controlled/living radical polymerization systems governed by the persistent radical effect [e.g., NMP and atom transfer radical polymerization (ATRP)].