Basf Aktiengesellschaft

Basell Polyolefine Gmbh

Gernot Koehler

Norbert Hasenbein

Thomas Muehlenbernd

Herbert Naarmann

Lothar Schlemmer

Roger G Klimesch

Juergen Schmidt-Thuemmes

Johannes Schlag

Andreas Deckers

Wilhelm Weber

Georg Groos

Wolfram Dietsche

Wolfgang Ball

Ernst Fischer

Frank Olaf Maehling

Juergen Schmidt-Theummes

In a process for the polymerization of ethylene and optionally further monomers in a high-pressure reactor at from 120 to 350&#xb0; C. and pressures of from 1000 to 4000 bar, hydrogen is intermittently introduced into the reactor.

Method for high pressure polymerization of ethylene

A copolymer of (a) from 96 to 99.6% molar of ethylene and (b) from 0.4 to 4% molar of a C,-C,-alkenoic acid or an ester thereof having not more than 14 carbon atoms or a mixture of these monomers, which copolymer may be prepared by polymerization in a continuously operated tubular reactor under a pressure of from 500 to 5,000 bar and at elevated temperature in the presence of free-radical initiators by feeding a mixture of the said reactants to the inlet port of the reactor only, restricting the temperature in a first reaction zone to approximately 240&deg; C. and, after the temperature has dropped by from 5&deg;to 20&deg; C., metering further initiator to the beginning of a second reaction zone and completing the reaction at a temperature of up to 300&deg; C.

Copolymer of (a) ethylene and (b) and alkenoic acid or a derivative thereof a mixture of said monomers

Novel ethylene homopolymers and ethylene copolymers which are suitable for film production and have a density from 925 to 940 kg /m.sup.3, a melt flow index (MFI) of &lt;1 g/10 min at 190.degree. C. and at an applied force of 2.16 kp can be prepared by free radical polymerization of the monomers at from 500 to 5000 bar and reaction temperatures T of from 40.degree. to 320.degree. C. by means of an initiator with virtually complete exclusion of oxygen in at least n=3 polymerization stages. In the first stage, the total amount or the predominant part of the monomers is subjected to the polymerization by means of part of the required initiator until the polymerization virtually comes to a stop. A further part of the initiator and, if required, of the monomers is then added to the mixture cooled to 20.degree.-60.degree. C. This process is repeated in the subsequent stages until the n th stage, at least the initiators used in the n th stage having a half-life temperature of from 90.degree. to 260.degree. C., and that the maximum reaction temperature T.sub.max being 270.degree. C. or higher, at least in the n th stage.

Ethylene homopolymers and ethylene copolymers and a process for their

Ionically crosslinked ethylene copolymers are prepared by reacting the corresponding ethylene copolymer in a mixing zone of a twin-screw extruder with a solid metal compound and subsequently pumping in water, and are used as adhesion promoters, laminating films, injection molded articles or cable sheathing.

Preparation of homogeneous ionically crosslinked ethylene copolymer in

A method of removing or of accumulating heavy metal ions from an aqueous solution by contacting the latter with an ethylene copolymer, in which a copolymer of ethylene with (meth)acrylic acid and a (meth)acrylate is used, in which the carboxyl groups may be neutralized by metal ions to an extent of 100% or less.

Method of removing or of accumulating heavy metal ions from an aqueous

Polyethylene and copolymers of predominant amounts of ethylene and minor amounts of comonomers which are polymerizable with ethylene are obtainable by free radical polymerization of the monomers under from 1,500 to 5,000 bar and at from 40.degree. to 250.degree. C. by means of an initiator with virtually complete exclusion of oxygen in not less than n=3 polymerization stages, by a method in which, in the first stage, the total amount of the predominant part of the monomers are subjected to polymerization using some of the initiator required, until said polymerization comes virtually to a stop, thereafter a further part of the initiator and, if required, of the monomers are added to the mixture, which has been cooled by 20.degree.-60.degree. C., and this process is repeated in the subsequent stages until the n th stage, with the proviso that the initiators used in the (n-1) th stage have a half-life temperature of from 80.degree. to 160.degree. C.

Preparation of polyethylene and copolymers of predominant amounts of

Aqueous dispersions of ethylene copolymer waxes, which dispersions are free-flowing at room temperature, contain a mixture of an ethylene copolymer wax having a high acid number and an ehtylene copolymer wax having a low acid number. The novel mixtures are particularly suitable as surface preservatives, as components in floor care agents or as sizes in textile finishing.

Wax dispersions having a high solids content

Ionically crosslinked ethylene copolymers prepared by mixing a carboxyl-containing copolymer with an aqueous metal salt solution in the reaction zone of a twin-screw extruder and transferring the product to a devolatilization zone, and are used as adhesion promoters, injection molded articles or laminating films.

Ionic crosslinking of an ethylene copolymer in twin-screw extruder

Aqueous synthetic wax dispersions which contain, as an essential component of the solid substance, a partially or completely neutralized copolymer of a C.sub.2 -C.sub.4 -olefin and an unsaturated mono- or dicarboxylic acid or dicarboxylic anhydride are prepared by neutralizing and dispersing the solid substance in an aqueous medium at above the melting point of the copolymer, by a method in which the processes of neutralization and of dispersion are carried out in one extruder or in a plurality of extruders connected in series.

Preparation of aqueous synthetic wax dispersions

A high molecular weight ethylene copolymer is prepared by high-pressure copolymerization of ethylene with an .alpha.,.beta.-ethylenically unsaturated carboxylic acid, carboxylic anhydride or a derivative thereof in the presence of a tertiary organic monoamine, preferably from 10 to 100 mol % thereof, based on the unsaturated carboxylic acid used, and can be used for preparing adhesion promoters and cable sheathing.

Preparation of amine-modified ethylene/carboxylic acid copolymers, such

Polyacetylene which is modified by reaction with a dienophilic compound, preparation of the said polyacetylene and its use for the production of moldings by processing by a thermoplastic method.

Modified polyacetylene

Highly electrically conductive copolymers of pyrroles and alkynes and/or aromatics, which possess good mechanical properties coupled with a well-balanced spectrum of properties, are prepared by anodic polymerization of the pyrroles and alkynes and/or aromatics in a polar solvent in the presence of a suitable conductive salt.

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Worms, Germany

Gernot Koehler