NMR studies of chlorinated poly(vinyl chloride) and polybutadiene

Molecular structures of chlorinated poly(vinyl chloride) and polybutadiene have been studied by high resolution NMR. The spectra of the chlorinated polymers give broad signals. New peaks appear in the lower fields of the CH2 and CHCl groups with increasing chlorine content. The chlorination of poly(vinyl chloride) takes place predominantly on CH2 rather than on CHCl, e.g., a 70% chlorinated polymer has about 10 mole‐% of CCl2 groups. Polybutadiene reacts first with chlorine by addition to give a head‐to‐head poly(vinyl chloride), and then the substitution of the hydrogen atom takes place. Chlorinated polybutadiene with 70% Cl has about 18 mole‐% of CCl2. The multiplets characteristic of spin‐spin couplings in the spectrum of the original poly(vinyl chloride) are still observed in that of the highly chlorinated product. This fact shows that a considerable number of poly(vinyl chloride) sequences of certain lengths persist in the highly chlorinated polymer.