Ethylene or propylene polymerization in the presence of macromonomers employing metallocene catalysts

Abstract

Co-polymerization of ethylene and branched unsaturated macromonomers was carried out with Ph2C(Flu,Cp)ZrCl2 or Et(Flu) 2ZrCl2, using MAO as co-catalyst. Propylene was also co-polymerized with macromonomer, employing Me2Si(2Me-Ind) 2ZrCl2/MAO for producing isotactic polypropylene. Polymerization behavior and co-polymer thermal properties were examined. The catalyst systems and the type of macromonomer affected polymer melting temperature and crystallinity degree. Using macromonomer with higher unsaturation content, a decrease of 6°C in co-polymer T m and around 50% in X c in comparison with ethylene homo-polymer was found. Surprisingly, an increase in the stereoregularity and in melting temperature was caused by the macromonomer incorporation in the polypropylene chains. © 2008 Koninklijke Brill NV.