LAUSR

Abstract Isotactic Polypropylene (iPP)-sepiolite nanocomposites were prepared by in situ polymerization using nanoclays as support of the catalytic system. This study proposes a method of immobilization that considers the use of the density of the polar groups present on sepiolite surface, to fix the co-catalyst. In addition, the resulting polymerization process defines the reaction time as a variable which will provide a mechanism for controlling the productivity of the reaction, making possible the obtaining of a masterbatch which may be useful in increasing the PP-clay compatibility in melt blending processes. The results of the proposed method have allowed not only the additivation of polypropylene during the synthesis, but also the structure control in terms of stereo-specificity and molecular weight, improving its final properties. Furthermore, in an effort to improve the impact properties of the iPP matrix, iPP copolymers were synthesized with 1-olefins of different chain lengths as co-monomers. The influence of the amount of co-monomer, amount of filler and type of branching obtained on the final properties of iPP nanocomposites were studied.