OXIDATION OF HYDROGEN-DONATING HYDROCARBONS FROM PETROLEUM RELATED TOITS INHIBITING EFFECT ON THE CHANGES IN DIELECTRIC-PROPERTIES

As the followup to our previous paper, multicomponent hydrogen-donatin g hydrocarbons derived from petroleum (HHAP) were oxidized at 160 degr ees C in air for 30 h compared with a conventional diphenylamine type antioxidant (Stealer), and the following results were obtained: (1) Ju dging from the changes in the dissipation factor, carbonyl absorbance by IR, acid value, and oxygen content by elemental analysis, HHAP was barely oxidized under these conditions, although n-paraffin wax was cl early oxidized. (2) Small amounts of oxygen-containing compounds (0.5 wt % in oxygen content), which are acidic materials but not carbonyl c ompounds, were formed from Stealer under these conditions. (3) In addi tion to the test results reported in our previous paper, it was reconf irmed by the humidity tests that the oxidation,of n-paraffin wax was s uperbly inhibited by the addition of HHAP, and the dissipation factor was kept low during the humidity tests. With regard to why HHAP was no t oxidized under these severe conditions, it was deduced that the free radicals formed from HHAP were stabilized by hydrogen liberated from HHAP itself.