Abstract: Ethylenically unsaturated monomers are polymerized in a gas-phase fluidized-bed reactor comprising a reactor space (1) in the form of a vertical tube, a calming zone (2) adjoining the upper part of the reactor space, a circulated gas line (3), a circulated gas compressor (4), a cooling apparatus (5), a gas distributor plate (6) which forms the lower boundary of the reactor space and, if desired, a flow divider (7), wherein the gas distributor plate (6) has a plurality of gas flow orifices (8) whose outlet sides are widened conically.

Abstract: Ethylenically unsaturated monomers are polymerized in a gas-phase fluidized-bed reactor comprising a reactor space (1) in the form of a vertical tube, a calming zone (2) adjoining the upper part of the reactor space, a circulated gas line (3), a circulated gas compressor (4), a cooling apparatus (5), a gas distributor plate (6) which forms the lower boundary of the reactor space and, if desired, a flow divider (7), wherein the gas distributor plate (6) has a plurality of gas flow orifices (8) whose outlet sides are widened conically.

Abstract: Ethylenically unsaturated monomers are polymerized in a gas-phase fluidized-bed reactor comprising a reactor space (1) in the form of a vertical tube, a calming zone (2) adjoining the upper part of the reactor space, a circulated gas line (3), a circulated gas compressor (4), a cooling apparatus (5), a gas distributor plate (6) which forms the lower boundary of the reactor space and, if desired, a flow divider (7), wherein the gas distributor plate (6) has a plurality of gas flow orifices (8) whose outlet sides are widened conically.

Abstract: Ethylenically unsaturated monomers are polymerized in a gas-phase fluidized-bed reactor comprising a reactor space (1) in the form of a vertical tube, a calming zone (2) adjoining the upper part of the reactor space, a circulated gas line (3), a circulated gas compressor (4), a cooling apparatus (5), a gas distributor plate (6) which forms the lower boundary of the reactor space and, if desired, a flow divider (7), wherein the gas distributor plate (6) has a plurality of gas flow orifices (8) whose outlet sides are widened conically.

Abstract: Ethylenically unsaturated monomers are polymerized in a gas-phase fluidized-bed reactor comprising a reactor space (1) in the form of a vertical tube, a calming zone (2) adjoining the upper part of the reactor space, a circulated gas line (3), a circulated gas compressor (4), a cooling apparatus (5), a gas distributor plate (6) which forms the lower boundary of the reactor space and, if desired, a flow divider (7), wherein the gas distributor plate (6) has a plurality of gas flow orifices (8) whose outlet sides are widened conically.

Abstract: Ethylene/.alpha.-olefin copolymers are prepared by catalytic dry-phase copolymerization of the monomers in a stirred or fluidized polymerization zone, transfer of the resulting mixture of solid copolymer and unconverted gaseous monomer into a let-down zone and separation of the mixture, after pressure reduction, into a gaseous phase and a solid phase, by a continuous process in which the solid phase is continuously flushed beforehand with gaseous ethylene and then flushed with a mixture of nitrogen and steam. The ethylene copolymers are very substantially free of residual monomers and odor and flavor substances.

Abstract: 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.

Abstract: Propylene/ethylene block copolymers are prepared by a process in which, in an agitated fixed bed comprising small polymer particles and in each case in the presence of hydrogen, first (I) propylene is homopolymerized from the gas phase, in a first polymerization zone, by feeding in a Ziegler-Natta catalyst, and then (II) the product obtained in the first polymerization zone is fed into a second polymerization zone, where a mixture of propylene and ethylene is polymerized with the propylene homopolymer present in the product from the first polymerization zone.

Abstract: The disclosure is directed to an improvement in the gas phase polymerization of propylene using a Ziegler-Natta catalyst in the presence of hydrogen wherein the gaseous propylene is withdrawn from the reactor, cooled and condensed and returned as a liquid to the reactor in order to regulate the polymerization temperature. The amount of the gaseous phase in the condenser-cooler-accumulator system is kept constant by regulating the amount of gaseous phase returned to the reactor.

Abstract: A process for the manufacture of a modified titanium-containing component of a catalyst for the polymerization of a .alpha.-monoolefins by the Ziegler-Natta method wherein (a) a compound containing titanium and (b) a compound containing phosphorus are ground dry in a vibratory ball mill. It is characteristic of the process that (1) a mill of relatively large useful volume is employed, (2) the mill is first charged with the compound (a) containing titanium, (3) while grinding the material at a low temperature, the compound (b) containing phosphorus is added gradually, thereafter (4) the material is gradually brought to a higher temperature, while continuing the grinding, and is kept at about this temperature for a prolonged period, then (5) a finely particulate 1-alkene polymer having a particular glass transition temperature and a particular intrinsic viscosity is added to the material and finally (6) the material is kept at a low temperature for a prolonged period, while continuing the grinding.

Abstract: A process for the manufacture of a modified titanium-containing component of a Ziegler-Natta catalyst for the polymerization of C.sub.3-6 .alpha.-monoolefins, wherein a specific titanium-containing compound and a specific phosphorus-containing compound are dry-milled at a specific grinding acceleration in a vibratory ball mill. The characteristic feature of the process of the invention is that a mill is used which has a specific useful volume and the mill is initially charged with a specific amount of the titanium-containing compound, which is milled at a low temperature while the phosphorus-containing compound is gradually added, whereupon milling is continued while the temperature of the process material is gradually raised to a specific value and maintained at said value for a specific period of time, whereupon, if desired, milling is again continued at a lower temperature for a specific period of time.

Abstract: A process for the manufacture of a modified titanium component for catalysts of the Ziegler/Natta type by milling a mixture of a titanium compound of the formula TiCl.sub.3 .13AlCl.sub.3 and an organic electron donor containing phosphorus and/or nitrogen atoms. The characterizing feature is that the mixture is first milled wet in a liquid inert hydrocarbon medium under specific conditions, then separated from the hydrocarbon medium and finally milled dry under specific conditions. Such modified titanium components give catalysts which provide particularly well reproducible results in the polymerization of .alpha.-olefins.

Abstract: A process for the manufacture of poly(.alpha.-olefins) by polymerization of .alpha.-olefins using a catalyst system comprising (1) a titanium-containing component of (1.1) a substance of the formula TiCl.sub.3 . 1/3 AlCl.sub.3 and (1.2) an organic electron donor containing phosphorus atoms and/or nitrogen atoms, ground together with said substance (1.1), and (2) an aluminum-containing component of a substance of formula Al(C.sub.n H.sub.2 ..sub.n.sub.+1).sub.3 or Al(C.sub.n H.sub.2..sub.n.sub.+1).sub.2 Cl, where n is an integer of from 2 to 6. The characteristic feature is that the catalyst system used is one in which the component (1.1) has been ground with component (1.2) without the use of auxiliaries or additives in a vibratory ball mill using specific steel balls and a specific grinding acceleration over a specific period of time at a temperature which is just below that at which the particles in the ground material begin to agglomerate.