Polymer degradation. V. Changes in molecular weight distributions during sonic irradiation of polyisobutene

摘要: Gel permeation chromatography was used to follow changes in the molecular weight distribution of a polyisobutene, initial Mv = 466,000, during degradation induced by sonic irradiation. Seven samples taken at times 200–163,500 sec. were studied. In general, steady decrease observed, although bimodal present after 20,000 Various measures inhomogeneity, Mw/Mn, U, etc., examined. The function, σn/Mw, where σn is standard deviation number distribution, considered as measure relative distribution. It shown be almost constant throughout degradation.