Radiation effects in polyisobutylene succinic anhydride modified with silica and magnetite nanoparticles

• The oxidation is initiated by the scission of double bonds and the bonds of tertiary carbons.
• PIBSA presents a single oxidation peak in nonisothermal CL spectra.
• PIBSA systems modified with Fe3O4 or SiO2 exhibit two oxidation peaks.
• The oxidation occurred at higher temperatures used by radiolysis radicals.
• The rates of oxidative degradation in PIBSA/Fe3O4 are higher as filler concentration increases.

Polyisobutylene succinic anhydride (PIBSA) was modified with nanoparticles of magnetite and silica for the appraising the modification in the thermal stability of organic component after gamma irradiation. Pristine anhydride was loaded with different amounts of nanofiller (1, 2 and 5 wt% of each oxide). Gamma exposure was performed in air at several doses: 10, 20, 50 and 100 kGy. The stability determinations were carried out by nonisothermal chemiluminescence in stationary air atmosphere. The presence of these oxides induces an increase in the oxidation level corresponding to their chemical availability as the filler amounts and exposure doses are enhanced. The oxidation takes essentially place on quaternary carbon atoms and double bonds, which was demonstrated by the presence of two chemiluminescence intensity peaks. The comparative analysis on the radiation oxidation of PIBSA modified with Fe3O4 and SiO2 is presented.