Abstract:
A pre-polymerized catalyst component for the polymerization of olefins endowed with high activity and morphological stability comprises (i) a non-stereospecific solid catalyst component comprising Ti, Mg and a halogen and having a porosity, due to pores with radius up to 1 μm, ranging from 0.2 to 0.8 cm 3 /g and (ii) an amount of an ethylene/alpha-olefm block (co)polymer ranging from 0.1 up to 5g per g of said solid catalyst component (i), said pre-polymerized catalyst component being characterized by a mercury porosity due to pores up to 1 μm of less than 70% the mercury porosity value of the said non-stereospecific solid catalyst component (i).
Abstract:
Catalyst components for the preparation of ethylene (co)polymers capable to produce polymers with high bulk density, to avoid the problems of formation of fines and that have a high activity are provided. Said catalyst components are characterized by comprising a non-stereospecific solid catalyst component, comprising a titanium compound and a magnesium dihalide, which is pre-polymerized with an alpha olefin CH2=CHRI wherein R is a C1-C8 alkyl group, to such an extent that the amount of the α-olefin pre-polymer is up to 100 g per g of said solid catalyst component.
Abstract:
The present invention relates to catalysts component for the polymerization of ethylene and its mixtures with olefins CH2=CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising Ti, Mg, halogen, and electron donor belonging to 1,2-diethers as internal electron donor compound. The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (co)polymers having narrow Molecular Weight Distribution (MWD) and high bulk density.