QUALIFICATION OF POLYPROPYLENE/CALCIUM CARBONATE NANOCOMPOSITES TO RADIATION DEGRADATION

Abstract

This paper describes the stability of irradiated polypropylene containing calcium carbonate nanoparticles. The main goal of this investigation is the characterization of additive effect on the polymer matrix, which is degraded in two different environments (air and water). The stability qualification of isotactic polypropylene modified with CaCO₃ nanoparticles were investigated by oxygen uptake at 190°C. The concentrations of filler are 0, 5, 10, 15, 20 and 25 % (w/w). Two types of covered calcium carbonate nanoparticles were used in the preparation of compounds Three irradiation doses (5, 15 and 25 kGy) were applied. The efficient protection of stabilizers that are present in the as-prepared formulations was emphasized by proper values of the kinetic parameters obtained for oxidation. The contribution of CaCO₃ nanoparticles to the oxidative process of i-PP is discussed. The technological applications of iPP/carbonate nanoparticles requires the decision on the temperature regime in connection with filler loading to satisfy simultaneously the manufacture conditions and the improved life of products.