The Effect of Calcium Carbonate on the Photo-Oxidative Behavior of Poly(butylene adipate-co-terephthalate)

Abstract

The aim of this work is to evaluate the influence of nanosized CaCO3 on the photo-oxidation of poly(butylene adipate-co-terephthalate) (PBAT)-based nanocomposites. The PBAT/CaCO3 nanocomposites are prepared by using a corotating twin-screw extruder with 0, 2, and 5 wt% of CaCO3. The films are obtained by film blowing process. Specimens of the nanocomposites and that of the pure polymer are subjected to accelerated aging with a cycle of 8 h of light at a temperature of 55 °C followed by 4 h condensation at 45 °C to evaluate the effects of the CaCO3 addition on the photo-oxidation of PBAT. The results indicate that the modulus and tensile strength of the nanocomposites are increased significantly after incorporation of nanosized CaCO3, but, however, the elongation at break remains almost unchanged. The presence of the calcium carbonate slightly increases the photo-oxidation rate of the matrix due to the presence of a stearate coating.