Basf Aktiengesellschaft

Basell Polyolefine Gmbh

Harald Schwager

Juergen Kerth

Bernd Lothar Marczinke

Sibylle Brosius

Klaus-Dieter Hungenberg

Erhard Seiler

Peter Koelle

Ralf Zolk

Lothar Schlemmer

Hermann Tatzel

Thomas Muehlenbernd

Hans-Joachim Mueller

Udo Haardt

Friedrich Domas

Patrik Mueller

Hans-Georg Braun

Werner Schoene

Klaus-Dieter Ruempler

Rueger Schlund

Susanne Hahn

Gerhard Kress

Guenther Schweter

Klaus Dieter Ruempler

Propylene-ethylene copolymers obtainable by three-step polymerization from the gas phase in an agitated fixed bed by means of a Ziegler-Natta catalyst system which, in addition to a titanium-containing solid component, also contains, as cocatalyst, an aluminum compound, where, in a first polymerization step, propylene is polymerized at from 60 to 90&deg; C. and at from 20 to 40 bar and at a mean residence time of the reaction mixture of from 0.5 to 5 hours, then, in a second polymerization step, a mixture of propylene and ethylene is polymerized onto the polymer obtained from the first polymerization step at from 40 to 110&deg; C. and from 5 to 30 bar, this pressure being at least 7 bar below the pressure in the first polymerization step, and at a mean residence time of the reaction mixture of from 0.2 to 4 hours, and then, in a third polymerization step, ethylene or a mixture of ethylene and propylene is polymerized onto the polymer obtained from the second polymerization step at from 40 to 110&deg; C. and from 5 to 30 bar and at a mean residence time of the reaction mixture of from 0.1 to 5 hours, the weight ratio between the monomers reacted in the first and second polymerization steps being adjusted to from 1:1 to 20:1 and the weight ratio between the monomers reacted in the first two polymerization steps and those reacted in the third polymerization step being adjusted to from 1:2 to 20:1.

Propylene-ethylene copolymers made from three different constituents

High-flow propylene/ethylene copolymers which have a melt flow index of from 2 to 200 g/min under a load of 2.16 kg at 230.degree. C. and which may be produced from the gas phase by polymerization in two stages in an agitated fixed bed in the presence of hydrogen acting as chain stoppage regulator and using a Ziegler-Natta catalyst system comprising a titaniferous solid component which contains a magnesium compound on finely divided silicon oxide or on finely divided aluminum oxide or on a finely divided aluminum silicate having the empirical formula SiO.sub.2.aAl.sub.2 O.sub.3, where a stands for a value between 0.001 and 2, and an aluminum component, by means of a procedure comprising a) a first polymerization stage in which propylene is polymerized under a pressure of from 20 to 40 bar and at a temperature of from 60.degree. to 90.degree. C., the ratio of the partial pressure of the hydrogen to that of the propylene being adjusted to from 1:100 to 10:100, followed by b) a second polymerization stage, which consists in the polymerization, at a temperature of from 40.degree. to 100.degree. C., of a mixture of propylene and ethylene and the addition thereof, in the form of polymerized units, to the polypropylene produced in the first polymerization stage, the pressure in this second polymerization stage being from 10 to 30 bar and at least 7 bar lower than that used in the first polymerization stage, while the ratio of the partial pressure of the hydrogen to that of the propylene is adjusted to from 2:100 to 12:100 and the ratio of the weight of monomer converted in the first stage to that of monomer converted in the second stage is kept within the range of 1:1 to 20:1.

Process for the production of high-flow propylene/ethylene copolymers

Copolymers of propylene with other 1-alkenes, obtainable by gas-phase polymerization of a mixture of propylene and another 1-alkene in the absence of a liquid reaction medium under a pressure of from 15 to 30 bar, at from 60.degree. to 90.degree. C. and with an average holdup time of the polymer of from 1 to 5 hours, with the aid of a Ziegler-Natta catalyst system which, besides a titanium-containing solid component, contains an aluminum component and an electron donor, with the temperature being chosen so that, under the preset pressure, no condensation of the monomer mixture takes place in the gas space and, moreover, the ratio of the partial pressures of propylene and the other 1-alkene is adjusted to from 5:1 to 100:1, are particularly suitable for producing sheets and shaped articles.

Process for preparing copolymers of propylene with other 1-alkenes

Propylene polymers have a molecular weight ratio Q (M.sub.w /M.sub.n) of from 6 to 30 and are obtainable by Ziegler-Natta polymerization in the presence of hydrogen as molecular weight regulator and are particularly suitable for the production of films and moldings.

Propylene polymers having a broad molecular weight ratio Q

High-flow blend of different propylene polymers

Propylene copolymers grafted with .alpha.,.beta.-ethylenically unsaturated carboxylic acids or derivatives and containing up to 35% by weight of other C.sub.2 - to C.sub.10 -alk-1-enes are obtainable by reacting the monomer to be grafted with a propylene copolymer at from 1 to 500 bar, where, in the absence of a free-radical initiator, from 0.01 to 1.0% by weight, based on the propylene copolymer, of the monomer to be grafted are admixed with the molten propylene copolymer, and the grafting reaction is carried out at from 210.degree. to 350.degree. C. The propylene copolymers according to the invention can be converted into crosslinked or crosslinkable propylene copolymers by admixing organic crosslinking agents.

Grafted, crosslinked and crosslinkable

Partially crosslinked olefin polymers are obtainable by reacting a) an ethylene polymer having a density of from 0.90 to 0.98 g/cm.sup.3 or b) a polymer of from 25 to 95% by weight of a propylene homopolymer and from 5 to 75% by weight of a propylene copolymer with polymerized C.sub.2 -C.sub.10 -alk-1-enes, the comonomer content being from 1 to 45% by weight, based on the total polymer, in the absence of free radical initiators, with from 0.001 to 5% by weight, based on the olefin polymer, of a bismaleimido compound of the general formula (I) ##STR1## where R is C.sub.1 -C.sub.20 -alkyl which may be interrupted by one or more oxygen atoms, or is C.sub.5 -C.sub.7 -cycloalkyl or C.sub.6 -C.sub.15 -aryl, each of which in turn may be substituted by one or more C.sub.1 -C.sub.10 -alkyl and/or C.sub.1 -C.sub.6 -alkoxy and/or C.sub.1 -C.sub.4 -dialkylamino groups, or is a radical of the following formula (II)

Olefin polymers partially crosslinked with bismaleimido compounds

A partially crosslinked polymer composition comprising

Partially crosslinked composition comprising polymers of propylene and

Partially crosslinked plastics materials having a melt flow index of from 0.1 to 100 g/10 min at 230.degree. C. and under a weight of 2.16 kg, containing

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Speyer, Germany

Harald Schwager