Ozone treatment of water‐soluble polymers. V. Ultraviolet irradiation effects on the ozonization of polyacrylamide

摘要

AbstractPolyacrylamide was ozonized in aqueous solution (at pH 2, 7, and 11) under UV irradiation with a low‐pressure mercury lamp. The breakage of the polymer chains by ozone was strongly accelerated by UV irradiation under acidic and neutral conditions. Formaldehyde was produced characteristically in the UV ozonization. From the correlation between the amount of formaldehyde and the number of breaks of polymer chains, it was presumed that one molecule of formaldehyde resulted from the chain breakage, at least under acidic conditions. The intensity of the UV absorption peak at 266 nm (285 nm in the UV ozonization at pH 2), which was presumed to be due to the carbonyl groups, namely, ketone and terminal aldehyde produced by ozonization, was very much stronger than that in simple ozonization. Oxamic acid and oxamide as end products were observed in the solution which was ozonized exhaustively under UV irradiatio