Influence of Phyllosilicate Structure on Performance of Polypropylene Nanocomposites Prepared via In-Situ...

This work explores the use of two different phyllosilicate structures (muscovite mica and bentonite) as co-support for in situ polymerization of propylene using Ziegler-Natta catalyst based on MgCl₂/TiCl₄ with electron donor for isotacticity control. It was observed along the experiments that the mass ratio MgCl₂:mica needs to be at least 3:1 in order to maintain a feasible catalyst activity. It was found through XRD, TEM, SEM and DMA that crystallinity of polypropylene composites is different according to the nature of phyllosilicates used and the mechanical performance of mica composites, as long as wettability and thermal stability were in general higher than those of PP/bentonite composites. Moreover, activity of MgCl₂:mica supported catalyst was higher than that co-supported on bentonite. Chemical modification in mica showed to improve in more than 500% the elastic modulus of PP/mica composites.