Patent ID: 6121391
Filing Date: 2000-09-19
Classification: C08F

Abstract:
A process for the preparation of polymers of vinylaromatic compounds at from - 80 to 150.degree. C. in the presence of metallocene catalyst systems, which process is carried out in one stage in a self-purging twin-screw extruder having corotating screws, and having an extruder barrel comprising a plurality of barrel sections, by first separately providingi) a first mixture in the form of a solution or suspension of one or more metallocene complexes of the formula II ##STR4## wherein R.sup.7 to R.sup.11 are each hydrogen, C.sub.1 -C.sub.10 -alkyl, 5- to 7-membered cycloalkyl, which in turn may carry C.sub.1 -C.sub.6 -alkyl groups as substituents, or C.sub.6 -C.sub.15 -aryl or arylalkyl, or two neighboring radicals together may furthermore form a cyclic group of 4 to 15 carbon atoms, or Si(R.sup.12).sub.3,R.sup.12 is C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl or C.sub.3 -C.sub.10 -cycloalkyl,M is a metal of subgroup III to VI of the Periodic Table of the Elements or a metal of the lanthanide series,Z.sup.1 to Z.sup.5 are each hydrogen, halogen, C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl, C.sub.1 -C.sub.10 -alkoxy or C.sub.1 -C.sub.15 -aryloxy, andz.sub.1 to z.sub.5 are each 0, 1, 2, 3, 4 or 5, the sum of z.sub.1 +z.sub.2 +z.sub.3 +z.sub.4 +z.sub.5 corresponding to the valency of M minus 1,andii) a second mixture comprising the vinylaromatic compounds and additionally (B) a compound capable of forming metallocenium ions, and (C) an aluminum compound of the formula IIIAlR.sup.13 R.sup.14 R.sup.15 (III)whereinR.sup.13 to R.sup.15 are each fluorine, chlorine, bromine, iodine or C.sub.1 -C.sub.19 -alkyl,subsequently, separately and at the same time, metering said first mixture and said second mixture into a first or a second barrel section of the extruder barrel,polymerizing the vinylaromatic compounds in the subsequent sections of the extruder barrel to give the polymer, and discharging the polymer from the extruder barrel at the last barrel section.