Thermal stability of isotactic polypropylene modified with calcium carbonate nanoparticles

Thermal stability of isotactic polypropylene with or without calcium carbonate nanoparticles (nCaCO₃) was investigated by chemiluminescence under isothermal regime at 190 °C. Two kinds of nCaCO₃ particles, i.e., (neat and stearic acid-coated ones) were used. The contents of nCaCO₃ within the iPP/nCaCO₃ nanocomposites were 5, 10, 15, 20, and 25% w/w. Several parameters, i.e., oxidation induction time, oxidation half-time, maximum oxidation time, and oxidation rate were used to quantify the thermal stability of both the neat and the nCaCO₃-filled iPP systems. The contribution of nanoparticles on the progress of oxidation is discussed. It has been found that the concentration of nCaCO₃ increases the stability of systems when nanoparticles were covered, while the filler consisted of unmodified particles, the decrease in thermal strength with the increase in filler concentration was noticed.