We employ the continuum approach in order to study the statistical character of the polymer resulting from a nonstationary polymerization with a firsthyphen;order termination process. Some authors have carried out theoretical investigations in connection with this problem by imposing conditions either on the monomer consumption or on the occurrence and nature of chain transfer. We deduce here the size distribution expression for the general case when spontaneous transfer and transfer through the monomer are simultaneously operative while the conversion is not limited to low values. The expressions for averages can be formally obtained from this result. Beyond the first average, however, the general expression gets too involved for convenient analysis. We investigate separately the effect of the two types of transfer on the size distribution and the averages in some typical cases. In the inhomogeneity versus conversion curves characteristic minima appear when only spontaneous transfer is operative, while the decrease is monotonic when transfer through the monomer alone is present. Finally, we compare the theoretical results for cumulative weight fraction with the experimental results of Pepper's group on the polymerization of styrene with strong sulphuric acid.
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