Evaluation of some commercial copper deactivators by chemiluminescence

Abstract

The effects of various transition metal stearates (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn), some commercial deactivators, and calixarene (cyclic oligomers of a phenol derivative) on the thermo-oxidative degradation of polypropylene were evaluated by the chemiluminescence method and comparison with oxygen uptake results. The time required to observe chemiluminescence was largely dependent on the kind of transition metal added to PP and the relative catalytic order was as follows: Co > Cr > Mn > Fe > Cu > Ni > V > Zn > Ti ⪢ pure. On addition of the copper deactivators, the time required to observe chemiluminescence was delayed and the inhibiting order was as follows: Mark CDA-1 > Chel-180 > OABH > Mark CDA-6. The order determined by the chemiluminescence method coincided fairly closely with those observed by the oxygen uptake method. Calixarene provides not only a copper deactivating function but also an antioxidizing one which was inferior to that of BHT.