Stabilization of isotactic polypropylene. Problems bound to the interactions of stabilizers with pigments and fillers

Abstract

The efficiency of conventional Hindered Amine Stabilizers (HAS) can be significantly reduced by their adsorption on other additives or fillers present in the polymer. The present article reports on the effect of titanium dioxide, phtalocyanine blue, and talc on the thermal and the photo stabilizations of isotactic polypropylene (iPP) by HAS. The durability of iPP was measured by the length of the induction period preceding the development of carbonyl groups by FTIR spectroscopy. The adsorption of HAS on pigments and fillers was revealed by the precise analysis of the carbonyl band of the ester group of HAS.