Basf Aktiengesellschaft

Burghard Schmitt

Juergen Hambrecht

Herbert Naarmann

Johann Swoboda

Rudolf Stephan

Georg Wassmuth

Claus Bernhard

Hermann Gausepohl

Gerhard Heinz

Graham E McKee

Helmut Barzynski

Helmut Tesch

Karl Gerberding

Rudolf H Jung

Konrad Mitulla

Hans Mittnacht

Ingo H Dorn

Jurgen Pohrt

Paul Witimer

Hansjoachim Maeder

The invention relates to a thermoplastic molding material of an elastomeric polymer A, a shell B grafted to the polymer A, and a copolymer C as rigid matrix. The amount of polymer A is 1 to 25 percent by weight based on the weight of A+B+C. It has a glass transition temperature, Tg, of less than 0.degree. C. and an average particle size of 200 to 750 nanometers (d.sub.50 value of the integral mass distribution) and is composed of: 50 to 99.9 percent by weight of at least one alkylacrylate with 1 to 8 carbon atoms in the alkyl radical and 0.1 to 5 percent by weight of a polyfunctional monomer which has a crosslinking action. Grafting shell B represents 5 to 40 percent by weight based on A+B+C and is composed of at least one of the monomers of the group of

Thermoplastic molding material

High molecular weight polyphenylene ethers are prepared from monohydric phenols by a conventional polycondensation, by a method in which the resulting polymers are reacted with an epoxide of the general formula (I) ##STR1## where R.sup.1 and R.sup.2 can be identical or different and are each alkyl, cycloalkyl, aryl, aryloxy, alkoxy or carboxyalkyl, each of which may contain a further epoxide group, or C.sub.3 -C.sub.20 -alkyl-substituted amino, or R.sup.1 is hydrogen and R.sup.2 is one of the above groups, or R.sup.1 and R.sup.2 form part of a cycloalkyl ring.

Poly (phenylene ethers) and their preparation

Thermoplastic mixtures based on macromolecular compounds and pyrrole polymers contain finely divided pyrrole polymers which are embedded in a matrix of the macromolecular compound. Such mixtures are prepared by a process in which solutions of the macromolecular compounds and compounds from the class consisting of the pyrroles are polymerized with an oxygen-containing oxidizing agent, and the resulting mixture is separated off from the solvent. Moldings obtained from such mixtures are used as electrical conductors or as electrodes.

Electrically conductive thermoplastic mixtures of macromolecular

A process for the preparation of branched block copolymers of from 60 to 95% by weight of a monovinyl-aromatic monomer and from 40 to 5% by weight of a conjugated diene by polymerizing the monomers in an inert solvent in the presence of a monolithium-hydrocarbon as the initiator, wherein, in a first process stage (a), from 50 to 80, or where necessary at most 90, % by weight of the total amount of monovinyl-aromatic compound are polymerized to virtually complete conversion in the presence of a relatively small amount of the monolithium-hydrocarbon. This stage is carried out by starting with from 30 to 70% by weight of the vinyl-aromatic monomer and adding from 70 to 30% by weight in the feed, during the polymerization, in such a way that the polymerization temperature, which at the start of the polymerization is from 30.degree. to 40.degree. C., is kept at from 45.degree. to 70.degree. C., with use of reflux cooling. After all the monomer feed has been added, the reaction temperature is lowered to 30.degree.-40.degree. C. by evaporative cooling. In a second process stage (b), an additional amount of initiator is added to the reaction solution, after which from 1 to 30% by weight of the total amount of monovinyl-aromatic monomer can be added, the sum of the amounts of monovinyl-aromatic monomer added in the first and second process stages being at most 90% by weight of the total amount of monovinyl-aromatic monomer. The monovinyl-aromatic monomer added in the second process stage is polymerized to virtually complete conversion, employing the temperature profile described for stage (a). In process stage (c), the remainder of the monovinyl-aromatic monomer and all of the conjugated diene are added, at least predominantly in the form of a mixture, and polymerized so that the reaction temperature does not rise above 90.degree.-110.degree. C. Finally, after virtually complete conversion of the monomers, and preferably without prior cooling, a suitable liquid polyfunctional coupling agent is run in undiluted and the mixture of the linear block copolymers obtained, which still contain active terminal lithium-carbon bonds, is coupled, with stirring, to form branched block copolymers. The products prepared according to the invention are used for injection molding.

Preparation of branched block copolymers

Graft copolymers comprising a crosslinked, saturated, elastomeric grafting base and a hard shell are prepared by incorporating thermolabile comonomers, as copolymerized units, into the grafting base during the preparation of the latter, in particular at a conversion of from 50 to 90%. During the subsequent grafting of the shell, the conditions used are such that the thermolabile comonomers incorporated as copolymerized units into the grafting base decompose into free radicals. This gives graft copolymers having improved mechanical properties, which copolymers also prove advantageous for the preparation of mixtures with other thermoplastics compatible with the graft copolymers.

Preparation of graft copolymers

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Worms, Germany

Burghard Schmitt