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3) Weast, R. C. Hondbook of Chemistry ond Physics, 70th ed.; CRC (4) Conway, B. E. Electrochemicol Doto; Elsevier: Amsterdam, 1952; pp p 760-1 (note that B requires p).The cyclohexane/polyoxyethylene(4)nonylphenol (E0(4)NP)/water system (2.8% EO(4)NP) with [H20] 1 [EO(4)NP] molar ratios between 0.1 and 6.9, has been investigated by electron spin resonance (ESR) spectroscopy using the following nitroxides: 3-carboxy-2,2,5,5-tetramethylpyrroIine-lsxyl (I), 2,5-dihydr~2,2,5,5-tetramethyl-3-[(triethylammonio)methyl]pyrrole-1-oxy1 bromide (11), and 5-doxylstearic acid (IV) as spin probes. For radicals I and I1 the nitrogen hyperfine splitting, aN, and the rotational correlation time, T~, have been analyzed, yielding information about the polarity and viscosity of their locations.At [H20]/[EO(4)NP] 6 0.3, the presence of "waterless" micellar aggregates in fast exchange (v, > 106 s-') with the monomer surfactant is evident. At [H20]/[EO(4)NP] = 0.6, the core viscoSity is at its maximum value and the exchange rate decreases below the limit of slow exchange (vex < lo6 s-I). Upon further increasing the water content, the core becomes more polar and less viscous, with these parameters approaching their values in bulk water. The effect of Cu(I1) ion (in an oil-soluble complex) on the spectra of radical II-confined to the water-pool-has been interpreted by using Leigh's theory, and the 'distance of closest approach" between these two paramagnetic species has been evaluated. This distance is considered to represent a measure of the penetrability of the micellar shell. Radical IV yielded anisotropic spectra in the aggregates with slow exchange. From their ESR parameters the order degree of the surfactant chains in the micellar shell has been evaluated. All results are consistent, indicating reduced penetrability and increased order with increasing dimensions of the water-pool.

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The polymerization of large cyclic vinyl compounds is of considerable interest in the interpretation of the mechanism of action of complex organometallic catalysts. Numerous vinyl compounds have been investigated up to now but no study has been made of compounds containing large rings. Studies on the isotactic polymerization of vinylcarbazole have brought to light very important facts permitting of a number of inferences as to the mechanism of isotactic polymerization. Despite the large molecular volume of vinylcarbazole and the steric hindrances that should be expected due to this, a study of the polymerization kinetics has revealed reaction rates similar to those observed in the polymerization of other monomers. The study of the polymerization of vinylcarbazole and of other monomers showed that the butyllithium‐titanium chloride catalyst belongs to the class of organometallic complexes that act either by a stepwise or ionic mechanism. The specific features of complex organometallic catalysts in the polymerization of vinylcarbazole are evidently associated with preliminary activation of the active centers during which activation of the monomer also takes place. The formation of polymers with an isotactic microstructure is due to one of the possible mechanism of the catalysis, namely, to nonstepwise action. In the polymerization of vinylcarbazole in the presence of organolithium compounds and titanium tetrachloride the microstructure of the resultant polymer and the rate of polymerization depend upon the formation of other than primary complex compounds. The microstructure of isotactic polyvinylcarbazole shows a particular shape of spherulites, depending upon the nature of the catalyst.