Ruhrchemie Aktiengesellschaft

Gunter Hetkamp

Hans-Walter Birnkraut

Siegfried Lutze

Josef Berzen

Peter Schneller

A high molecular weight copolymer of ethylene and a C.sub.3 -C.sub.20 .alpha.-olefin which, after being molded at room temperature and pressure-free tempered at 120 to 250.degree. C. and thereafter cooled, provides molded articles having an ultimate tensile strength of more than 200 kg per square centimeter measured at 120.degree. C. and an impact strength of more than 200 kg cm/cm.sup.2 measured at 23.degree. C.; a process for the preparation of such a copolymer by a Ziegler catalysis which process is characterized in that the catalyst which is employed is one obtained by reducing a titanium-(IV)-halide with an organo-aluminum compound in an inert solvent such that the concentration of titanium-(III)-halide so formed amounts to 30 to 200 m mol/liter solvent, the C.sub.3 -C.sub.20 .alpha.-olefin is employed in an amount of 0.05 to 5 weight percent based upon the weight of the ethylene and the catalyst is either initially contacted with C.sub.3 -C.sub.20 .alpha.-olefin in the absence of ethylene and thereafter contacted with the ethylene or, is initially contacted with a mixture of C.sub.3 -C.sub.20 .alpha.-olefin and ethylene; and a catalyst for such polymerization.

Growing community of inventors

Dinslaken, Germany

Gunter Hetkamp