AbstractThermal degradation of polyvinylimidazoles on potassium bromide plate has been studied. At 300°C heat treatment, the occurrence of oxidation and dehydrogenation leads to the formation of saturated ketones and unconjugated CC bonds in the polymer backbone, respectively. The combination of the two types of reactions also yields α,β‐unsaturated keto compounds. Then at prolonged heat treatment at 300°C, cleavage of imidazole rings also occurs and α,β‐unsaturated cyano structures are formed. At 400°C, a new class of compound, carbodiimides, is being produced while the amount of the α,β‐unsaturated cyano compounds is greatly reduced. Similar to polyacrylonitrile, ladder‐type structures for degraded PVI(1) and PVI(4) are
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