Abstract: In order to prepare thermoplastic molding materials ofA) 5-95% by weight of a modified polyphenylene ether,B) 5 to 95% by weight of a thermoplastic polyamide,C) 0 to 25% by weight of an impact-modifying rubber, andD) 0 to 50% by weight of auxiliaries and/or additives,the components A and B and if necessary the components C and D are fed individually at one or more points into an extruder, mixed with one another, and melted. The component A present in a pulverulent consistency is compacted and/or sintered under pressure and if necessary with the addition of heat, preferably at a pressure corresponding to a nip pressure of 1 to 100 kn/cm to form a porous compact before it is fed into the extruder. The compact is then modified and added as granules to the feed zone of the extruder. In this way the proportion of the fines in the polyphenylene ether is considerably reduced, so that there is virtually no further danger of dust explosions.

Abstract: In order to prepare thermoplastic molding materials from pulverulent polyphenylene ethers and aromatic vinyl polymers by melt extrusion, the pulverulent polyphenylene ether is first of all compacted and/or sintered under pressure and if necessary with the addition of heat, preferably under a pressure corresponding to a nip pressure of from 1 to 100 kN/cm, to form a porous compact. The compact is then fed in the form of agglomerates having a particle size of from about 0.5 mm to about 20 mm into an extruder or the like, mixed with the aromatic vinyl polymer and if desired further components, and melted. In this way the proportion of the fines in the polyphenylene ether is considerably reduced, with the result that there is virtually no further danger of dust explosions. Further advantages include improved ease of metering and reduced electrostatic charge of the agglomerates. The extruded molding materials have good mechanical properties and also high thermal stability.

Abstract: Polyphenylene ethers are prepared from monohydric phenols by oxidative coupling with oxygen-containing gases in the presence of an oxidation catalyst in an organic solvent by carrying out the polycondensation in the presence of a defoamer.

Abstract: A process for preparing polyphenylene ethers from monohydric phenols which have alkyl substituents in both ortho positions and possibly also in one meta position but not in the para position, by oxidative coupling with oxygen-containing gases in the presence of an oxidation catalyst and of an electrically conducting compound which counteracts the electrostatic charge in the reaction mixture, in organic solution, comprises using as electrically conducting compound a salt of a carboxamide derivative of the formula I ##STR1## or mixtures of such salts, where R.sup.1 is a saturated or singly or multiply unsaturated aliphatic group which can have a terminal phenyl group and which contains a total of 8-30 carbon atoms, it also being possible for these carbon atoms to be interrupted by isolated oxygen atoms,R.sup.2 is hydrogen or C.sub.1 -C.sub.4 -alkyl,A is an aliphatic, araliphatic or cycloaliphatic or aromatic bridge of up to 10 carbon atoms,n and m are each 1 to 3,Q.sup..sym.

Abstract: A novel, optically transparent, isotropic molding for optical purposes which is free of orientation birefringence consists of a mixture of polyphenylene ethers, vinylaromatic polymers and additives. The novel molding contains traces of novel diphenoquinone and/or diphenohydroquinone derivatives as additives and may also contain novel ammonium salts of sulfuric acid half esters of diphenohydroquinones as further additives. The novel molding has a yellowness index (YI) of from 40 to 90. It can be produced in a simple manner by injection molding processes. The novel molding in the form of a circular disk having a central hole is very useful as a dimensionally stable substrate of audio compact disks (CD), audiovisual compact disks (CDV), laser-optical computer disks and magneto-optical computer disks, and data media of this type which contain these novel dimensionally stable substrates have particularly advantageous performance characteristics.

Abstract: High temperature resistant polysulfone-polyimide block copolycondensates suitable for example for producing shaped articles are composed of at least one polyarylene ether sulfone block comprising units of the structure ##STR1## and at least one polyimide block comprising units of the structure ##STR2## where R.sup.1 and R.sup.2 are identical or different and each is hydrogen or methyl and X is methylene or 1,2-ethylene, and are prepared by condensing conventionally obtained amine-terminated polyarylene ether sulfone blocks with polyimide blocks in the melt.