The ultimate success of living-radical polymerizations will depend on whether they can be used to make materials with unique properties in an economical and acceptable manufacturing process. We report a major step in this direction for the SFRP process by demonstrating that a miniemulsion process can be used to polymerize monomers to high conversion with a high degree of livingness and that this process can be used to synthesize block copolymers. The key to the polymerizations is the use of a nitroxide-terminated oligomer to initiate the miniemulsions. Miniemulsions are performed at 135 °C to greater than 99% conversion to give polystyrenes with polydispersities between 1.15 and 1.25. Chain extension studies show these materials to have a high degree of livingness. Reaction of these polystyrene latexes with n-butyl acrylate lead to the first block copolymers completely made under SFRP miniemulsion conditions.

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The phototransposition reactions in acetonitrile of p-, m-, and o-methylbenzonitrile have been studied. Any one of the three is converted to the other two by either a 1,2-or 1,3-isomerization in a primary photochemical step. However, the reactivities are quite different with the relative values for para:meta:ortho ) 32:4:1. For both the para and meta isomers, extended irradiations approach a calculated steady-state composition of para:meta:ortho ) 3:20:77. Quenching of the excited triplet state of the para and meta isomers with 2,4-dimethyl-1,3-butadiene indicates that these reactions are occurring from the excited singlet state. Irradiation of selectively labeled 2,6-dideuterio-4-methylbenzonitrile demonstrates that only the cyano-substituted carbon undergoes migration.

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