AbstractApparent quantum yields for the random scission of poly(α‐methylstyrene) in solution by 2537 A. radiation were shown to be solvent‐dependent, indicating that processes other than the direct photolysis of the polymer are taking place. Quantum yields on the order of 10−3 scissions per quantum absorbed by the polymer were found in benzene, dioxane, cyclohexane, and methylene chloride and about 0.2 in chloroform and carbon tetrachloride; the quantum yields were unaffected by oxygen. In carbon tetrachloride, the quantum yields decreased slightly with increasing polymer concentration. Ethanol and cyclohexane were inhibitors for the photolysis in carbon tetrachloride, while the latter solvent acted as a sensitizer in cyclohexane. By comparison with model compounds irradiated in carbon tetrachloride, it was shown that an early step in the photolysis of poly(α‐methylstyrene) in this solvent involves reaction with a main‐chain methylene group and eventual substitution with a trichloromethyl group.
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