| abstract |
Ti, Mg, Cl, and optionally OR I groups, where R I is a C 1 to C 20 hydrocarbon group in an amount that gives an OR I / Ti molar ratio lower than 0.5. ), Including the following properties:-a surface area lower than 80 m < 2 > / g as measured by the BET method;-a total porosity in the range of 0.60 to 1.50 cm < 3 > / g as measured by the mercury method (P < T >) A difference in (P T -P F ) higher than −0.1, where P T is the total porosity and PF is the porosity due to pores with a radius of 1 μm or less; A catalyst component comprising: an amount of Ti in the catalyst component of less than 10% by weight, based on weight. Such catalyst components exhibit high form stability under low molecular weight ethylene polymerization conditions while simultaneously maintaining high activity characteristics. [Selection figure] None |