ANTIOXIDANT DEPLETION AND OIT VALUES OF HIGH IMPACT PP STRANDS

作     者：Werner W.Müller Ines Jakob Chunshan Li Renate Tatzky-Gerth 

作者机构：Federal Institute for Materials Research and Testing(BAM)D-12200 BerlinGermany 

出 版 物：《Chinese Journal of Polymer Science》 (高分子科学（英文版）)

年 卷 期：2009年第27卷第3期

页      面：435-445页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：Polypropylene Stabilizers Oxidative resistance Antioxidant depletion Oxidative induction time 

摘      要：The service life of a polyolefin product depends to large extent on the type and amount of the antioxidants added. During the manufacturing,storage and use of the product the antioxidants are depleted by physical processes and chemical degradation,and this impairs its long-term *** initial and in-use oxidation stability is often characterized and monitored by the measurement of the oxidative induction time(OIT),and service life predictions are based on the rate of decrease of the OIT *** study the correlation between the OIT value and the actual antioxidant concentration,eight random arrays of high-impact polypropylene(PP)strands stabilized using six different antioxidant packages(composed of Irgafos 168,Irganox 1010 and 1330,Chimassorb 944)were immersed in hot water(80℃and 90℃)and oven aged in air (80℃)for more than two years,and the change of OIT values and antioxidant concentrations was *** phosphitic and phenolic stabilizers water immersion is generally a more critical aging condition than oven aging in air,while for the hindered amine stabilizers(HAS)the opposite was *** expected,a linear correlation between OIT values and concentrations was found for the classical package of phosphitic and phenolic *** the case of Irganox 1330,the change of the OIT values during aging was considerably slower than the change of *** when zero concentration was reached according to the vanishing peak height in the chromatogram,a considerable OIT value was still *** may be due to unidentified degradation products of Irganox 1330 which still act as antioxidants in the long *** of HAS(Chimassorb 944)seems to enhance the initial OIT of stabilized phenolic samples and the long-term effectiveness of the phenolic stabilization under air oven aging ***,the marked long-term effectiveness of the HAS itself and the slow change with time of the concentration were not detectable by OIT measurements