Basf Aktiengesellschaft

Badische Anilin- & Soda-fabrik Aktiengesellschaft

Dieter Stein

Gerhard Fahrbach

Erhard Seiler

Karl Gerberding

Hermann Gausepohl

Gerhard Heinz

Adolf Echte

Rolf Wurmb

Manfred Walter

Rainer Theysohn

Robert Bachl

Rudolf H Jung

Franz Haaf

Georg Falkenstein

Joachim Kunde

Ernst Schoen

Konrad Richter

Dirk Juza

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.

Process for producing ethylene polymers and copolymers by means of a

A process for the preparation of propylene homopolymers or copolymers by polymerizing the monomer or monomers in the gas phase in a centric stirred bed of finely divided polymer, with removal of the heat of polymerization by evaporative cooling, the temperature in the polymerization zone being regulated by measuring the temperature continuously and causing any change therein to trigger a change in the amount of liquid monomer, evaporating in the reaction zone, which is introduced per unit time, in which process (1) the radius and height of the centric stirred bed are in a particular ratio to one another, (2) the finely divided polymer in the centric stirred bed is caused to move upward in the peripheral zone of the bed and downward in the central zone of the bed, (3) the temperature in the polymerization zone is regulated by simultaneously measuring it at (3.1) one or more points of the inner part of the stirred bed and (3.2) one or more points of the outer part of the stirred bed and (4) the actual temperatures T determined simultaneously at the individual points of measurement are combined to give a temperature parameter T.sub.M and the difference of this parameter from the intended value triggers the regulating sequence, or the temperature differences .DELTA.T between the actual and intended temperatures, measured simultaneously at the individual points of measurement, are combined to give a difference parameter .DELTA.T.sub.M and this parameter triggers the regulating operation.

Preparation of propylene homopolymers or copolymers

A process for the manufacture of high impact and translucent polystyrene, in which, in a first stage, styrene is prepolymerized in mass or in solution in the presence of a rubber, and the polymerization is then completed in mass, in solution or in aqueous suspension. The prepolymerization is taken to a stage where the amount of styrene converted is from 3 to 10 times the amount of the elastomer constituent of the rubber, and at this conversion the disperse soft-component phase formed should have a mean particle size of less than 1 .mu.m and should contain from 35 to 65% by weight of free or chemically bonded polystyrene segments. The translucent styrene polymers of high impact strength may be used for packaging purposes.

Manufacture of high impact and translucent styrene polymers

Branched block copolymers of from 60 to 95 percent by weight of a monovinyl-aromatic compound and from 40 to 5 percent by weight of a conjugated diene. The branched block copolymers have a structure of the general formula

Branched block copolymers and their manufacture

Branched block copolymers of from 60 to 95 percent by weight of a monovinyl-aromatic compound and from 40 to 5 percent by weight of a conjugated diene. The copolymers have a structure of the general formula

Polyurethane compositions -- which may or may not be foamed -- having improved mechanical properties are manufactured from organic polyisocyanates, polyhydroxy compounds and one or more at least partially crosslinked, particulate polymers of particle size from 500 to 5,000 A, of which polymer from 1 to 40% by weight are dispersed in the polyhydroxy compound.

Manufacture of polyurethane compositions

A process for the manufacture of block or graft copolymers of polyalkylene oxides and vinylaromatic polymers or diene polymers. The block or graft copolymers are manufactured by reacting vinylaromatic polymers or diene polymers bearing methyl methacrylate end groups with polyalkylene oxides bearing alkali metal alcoholate end groups. The block or graft copolymers may be used as antistatic agents for plastics, as coating materials for non-woven webs, as intermediates in the manufacture of polyurethanes and as surfactants, protective colloids or emulsifiers.

Block or graft copolymers of polyalkylene oxides and vinylaromatic or

This invention relates to a process for the manufacture of graft copolymers based on methyl methacrylate polymers. The methyl methacrylate polymer is reacted with a high molecular weight organic compound containing at least one alkylene oxide unit having an alkali metal alcoholate end group, during which reaction transesterification occurs to eliminate alkali metal methoxide and cause chain joining. The graft copolymers may be used for the production of shaped articles or coating compositions and as additives, antistatic agents or adhesion promoters for plastics materials.

Graft copolymers based on methyl methacrylate polymers

Reinforced plastics containing an addition of from 0.05 to 2% w/w of a styrene oligomer.

Reinforced thermoplastics

Manufacture of low molecular weight block copolymers of vinyl or diene monomers and alkylene oxides. In a first stage, the vinyl or diene monomers are polymerized as chain stopper, and in a second stage, one or two blocks A are added thereto by the addition of further alkylene oxide. The resulting block copolymers may be used as prepolymers for the manufacture of polyurethanes, as dispersing agents for dyes, as antistatic agents, emulsifiers, surfactants or as paper and textile finishing agents.

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Limburgerhof, Germany

Dieter Stein