Ultrasonic degradation of polymer molecules in solution: Some comments on recent papers

Recent papers on the ultrasonic degradation of polymer molecules in solution are discussed. It is pointed out that the use of the Staudinger equation to derive weight‐average degrees of polymerization from the viscosities of benzene solutions of polystyrenes is a source of error, since these solutions have been found to obey the Houwink equation. Some measurements of degradation rates by the use of diphenyl picryl hydrazyl as a free radical scavenger are considered, and it is concluded that they can be fitted almost equally well by two different rate equations.