摘要:
A process for the continuous preparation of finely divided homopolymers and copolymers of ethene by catalytic polymerization in a circular tube reactor using a liquid alkane as reaction medium in which the ethene or ethene/comonomer mixture to be polymerized is present in dissolved form and the polymer formed is present in suspended form and running the reaction mixture as a cycle stream to which the feed materials are added by bleeding in and from which the polymer formed is withdrawn by bleeding out reaction mixture, comprising (a) maintaining the mean concentration C.sub.m of polymer in the cycle stream at a value within a certain range and (b) effecting the bleeding out of reaction mixture at a point of the cycle stream at which the concentration of polymer has a value which is lower than the mean concentration C.sub.m by a distinct and definite amount.
摘要:
A process for the preparation of ethylene homopolymers, and ethylene copolymers with minor amounts of higher .alpha.-monoolefins, by polymerizing the monomer or monomers by means of a supported catalyst (1) containing a chromium-hydrocarbon complex (1.2) on an inorganic oxide carrier (1.1), wherein (1) a supported catalyst is employed which contains (1.2) a chromium-hydrocarbon complex of the formula RCrACrR, where R is a cyclic and/or open-chain hydrocarbon, or hydrocarbon radical, of 2n and 2n+1 carbon atoms respectively and having from 1 to n non-cumulated double bonds, n being from 2 to 10, Cr is chromium and A is cyclooctatetraene, a divalent n-octatetraene radical or alkyl-substituted homologs thereof, on (1.1) a particular inorganic oxide carrier, with or without (2) a co-catalyst chosen from a particular group of alkyl-aluminum compounds. The process gives polymers having a particularly broad molecular weight distribution.
摘要:
The homopolymerization and copolymerization of ethene are carried out using a Ziegler catalyst system consisting of(1) a transition metal catalyst component,(2) an organoaluminum catalyst component and(3) an organohalogen catalyst component.In the homopolymerization or copolymerization, the solid-phase product (VI) used as (1) is the product which has been obtained by a method in which (1.1) first (1.1.1) an inorganic oxidic substance (I) as the carrier and (1.1.2) a solution (II) of (IIa) a certain oxahydrocarbon and (IIb) a vanadium trichloride/alcohol complex and (IIc) a silicon or boron compound are combined with formation of a suspension (III), the latter is evaporated down to form a solid-phase intermediate (IV), and (1.2) then (1.2.1) the intermediate (IV) obtained in (1.1) and (1.2.2) a dissolved organoaluminum compound (V) are combined with the formation of a suspension, the solid-phase product (VI) obtained as the suspended substance being the transition metal catalyst component (1).
摘要:
Homopolymerization and copolymerization of ethene are carried out using a Ziegler catalyst system consisting of (1) a transition metal catalyst component prepared by a method in which (1.1) first (1.1.1) an inorganic oxide substance (I) as a carrier and (1.1.2) a solution (II) of (IIa) a certain oxahydrocarbon and (IIb) a mixture of (IIb1) a vanadium trichloride/alcohol complex, (IIb2) a titanium trihalide or titanium trihalide/alcohol complex and, if desired, (IIb3) a zirconium tetrahalide, are combined with formation of a suspension (III), the latter is evaporated down to form a solid-phase intermediate (IV), (1.2) then (1.2.1) the solid-phase intermediate (IV) obtained from (1.1), and (1.2.2) a dissolved organoaluminum compound (V), are combined with formation of a suspension, the resulting suspended substance being a solid-phase product (VI), (2) an organoaluminum catalyst component and (3) an organohalogen catalyst component. In this process, the transition metal catalyst component (1) used is one prepared by a method in which (1.3) in addition (1.3.1) the product (VI) obtained from (1.2) is reacted with (1.3.2) oxygen, the resulting solid-phase end product (VII) being the novel transition metal catalyst component (1).