1-Olefin polymer wax, and a process for the preparation thereof

A process for the preparation of a 1-olefin polymer wax comprising units derived from a 1-olefin of the formula RCH.dbd.CH.sub.2 in which R denotes an alkyl radical having 1 to 28 carbon atoms, having a molecular weight M.sub.w of from 1,000 to 25,000, a molecular weight distribution M.sub.2 /M.sub.n of from 1.8 to 4.0, a viscosity number of from 2 to 60 cm.sup.3 /g and a melting range of from 120 to 160.degree. C., a melt enthalphy H of greater than 80 J/g, a drip point range of from 120 to 160.degree. C. and a melt viscosity of from 100 to 20,000 mPa.s at 170.degree. C., by polymerization of a 1-olefin of the formula R--CH.dbd.CH.sub.2 in which R is an alkyl group having 1 to 28 carbon atoms, or copolymerization of this olefin with ethylene at a temperature of from -60 to 200.degree. C., at a pressure of 0.5 to 120 bar, in solution, in suspension or in the gas phase, in the presence of a catalyst comprising a transition metal compound and an activator, a metallocene being the transition metal compound and an aluminoxane being the activator, which process comprises:

• carrying out the polymerization in the presence of a catalyst whose transition metal component is a metallocene of the formula (I) ##STR5## in which Me is a metal from group IVb or Vb of the Periodic Table of the Elements,
• R.sup.1 and R.sup.2 are identical or different and denote a C.sub.1 -C.sub.10 alkyl group, a C.sub.6 -C.sub.10 -aryl group, a C.sub.2-C.sub.10 -alkenyl group, a C.sub.7 -C.sub.40 -aralkyl group, a C.sub.8 -C.sub.4 --aryl-alkenyl group or a halogen atom, R.sup.3 is a linear C.sub.1 -C.sub.4 -or a cyclic C.sub.4 -C.sub.6 -hydrocarbon radical which optionally contains at least one heteroatom in the chain as a bridging unit;
• R.sup.4 and R.sup.5 are identical or different and denote a mononuclear or polynuclear hydrocarbon radical which is capable of forming a sandwich structure together with the central atom;
• 5minutes to 60 minutes before the polymerization, pre-activating said metallocene at a temperature of from -78 to 100.degree. C. using an aluminoxane of the formula (II) ##STR6## for the linear type and/or of the formula (III) ##STR7## for the cyclic type, where, in the formulae II and III, R.sup.7 denotes a C.sub.1 -C.sub.6 -alkyl group and p is an integer from 5 to 40, and where the activator is likewise an aluminoxane of the formula II or III;
• and, during the polymerization, adding hydrogen in the 1-olefin:H.sub.2 molar ratio from 3 to 3,000.