The kinetics of the uncatalyzed oxidation of alkali cellulose by molecular oxygen (autoxidation) have been studied. It is shown that a linear relationship exists between the copper number of cellulose regenerated from a freshly prepared alkali cellulose and the initial rate of autoxidation of the alkali cellulose. As reaction proceeds, however, the rate approaches a constant value which, under given conditions, is independent of the initial copper number. Peroxides are formed during the reaction, to an extent which is dependent upon trace concentrations of various heavy metals. The effects of temperature, oxygen pressure, and alkali cellulose composition on reaction rate are discussed. The results are consistent with the present picture of autoxidation processes being free-radical-propagated chain reactions.

The previous paper in this series discussed the uncatalyzed autoxidation of alkali cellulose and suggested that the reaction proceeds via a chain mechanism involving transient free radicals.The present paper describes the effect of certain transition metal catalysts on the kinetics of oxygen absorption and cellulose depolymerization. It is further shown that the reaction is subject to catalysis by substances which generate free radicals and by the presence of certain other autoxidizable substances. Silver and gold compounds behave as inhibitors, as do some typical organic antioxidants. The results provide further evidence for the free-radical chain character of the reaction. Possible depolymerization processes are discussed in terms of this approach.

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The polymerization of styrene, methyl methacrylate and acrylonitrile is initiated by the amide ion in liquid ammonia, the product being a low molecular weight polymer containing one NH, group p r polymer chain.Other negative ions such as the triphenyl methyl anion also initiate polymerization. Certain disubstituted olefines such as a-methylstyrene and diphenyl ethylene do not undergo polymerization but react with the amide ion forming intensely red-coloured solutions:A mechanism for the polymerization is suggested, and the predicted dependence of molecular weight upon the concentration of potassium amide and of monomer (styrene) is in reasonable agreement with that observed in the concentration ranges studied in detail.The energetics of the initiation and termination reactions are discussed and the observed behavior of various monomers with a series of different anions is semi-quantitatively explained.In the course of studies of the formation of the NH, radical by oxidation reduction reactions in liquid ammonia solutions, and of the reactions of this radical, we have found that the amide ion NH,-