IONIC REACTIONS IN UNSATURATED COMPOUNDS .4. VINYL CHLORIDE

Mass spectrometric studies of ion-molecule reactions in vinyl chloride have resulted in the identification of three ionic polymerization sequences (Chemical Equation Presented) In most cases the indicated condensation reactions proceed with elimination of HCl or C2H2. Isotopic studies show that the principal reaction of low velocity parent ions is charge transfer, the rate constant for this process being some 30 times larger than the summation of rates for other ion-molecule reactions It is further observed that vinyl chloride parent ions produced directly by electron impact react to give a distribution of condensation products which is substantially different from that which results from the reactions of parent ions formed by charge transfer. This is interpreted in terms of differences in the internal energy of the collision complexes formed by the two types of reactant ions. An examination of the dependence of the product distribution from this reaction on both internal and translational energy of the reactants shows that the former is the more important factor in this system. The results of the present investigation are compared with data on ionic processes in vinyl chloride obtained by other techniques.