Hoechst Aktiengesellschaft

Detlef H Skaletz

Horst Heckel

Bernhard Pfeiffer

Joachim Heydweiller

Anne Texier

Karin Mehmke

Michael Haubs

Gerhard Buhr

Hartmut Fischer

Gerhard Lohaus

Friedrich Herold

Jurgen Sander

Andreas Lucke

Claus-Peter Krieg

Bruno Wagner

Ludger Czyborra

Wildhardt Juergen

Michael Wernicke

This invention relates to an electrically conductive shaped article made from thermoplastic materials which are reinforced with glass and steel fibers wherein said fibers are incorporated into the thermoplastic material by pultrusion. The amount of glass fibers incorporated into the thermoplastic material is such that the specific conductivity is at least 10% greater than in a shaped article in which the glass fibers are replaced by thermoplastic material. The shaped article can be used for shielding an article from electromagnetic radiation.

Electrically conductive shaped articles

To prepare a glass fiber-reinforced composite material, a glass fiber strand is drawn through an agitated aqueous powder dispersion of a coupling agent over a deflection body, the water is removed, the powder is melted onto the glass fiber strand and the pretreated fiber strand is subsequently impregnated with polyolefins by means of melt pultrusion.

Process for making glass fiber-reinforced composite material

To produce fiber-reinforced composites, a continuous fiber strand is pulled through an agitated aqueous thermoplastic powder dispersion via deflectors. Following removal of the water phase the thermoplastic powder is heated and melted onto the fibers. Finally the fiber strand is impregnated with a thermoplastic melt by melt pultrusion.

Production of fiber-reinforced composites by pultrusion with

In granules of fiber-reinforced thermoplastic material, a multiplicity of individual filaments of the reinforcing fiber (e.g. glass) are arranged in parallel in a matrix of the thermoplastic material (e.g. polypropylene). The fiber length corresponds to the granule length and is in the range from 3 mm to 8 mm. The melt viscosity of the thermoplastic material is above 100 Pa.s, the diameter of the granules (measured perpendicular to the fiber direction) is 1.7 to 5 mm and the ratio diameter:length of the granules is 0.4 to 1.66.

Granules of fiber-reinforced thermoplastic

An electrically conducting molding comprises thermoplastic material which is reinforced with metal fibers. A metal covering is connected to the molding by three-cornered prongs and serves as an electric contact.

Molding with electrical contact

An injection molding which is built up from a thermoplastic material and glass fibers where the glass fibers have a fiber length of at least 5 mm and are present in an amount of 2 to 8% by weight, based on the total weight of the glass fibers and thermoplastic material. The injection molding has an impact strength at 23.degree. C. of at least 170 kJ/m.sup.2 and an impact strength at -30.degree. C. of at least 140 kJ/m.sup.2. The injection molding material is distinguished by a significant improvement in its impact strength, together with an increased heat resistance compared with injection moldings of simple thermoplastic materials which are not reinforced with fibers.

Injection molding of thermoplastic material including from 2 to 8% by

A process which includes comminuting a first thermoplastic material, e.g. polypropylene, reinforced with short glass fiber (10-400 .mu.m). 100 parts by weight of the comminuted material are mixed with 11-43 parts by weight of chips of a second thermoplastic material, which is reinforced with long glass fiber (about 10-20 mm). The melts of the two thermoplastic materials should be mutually mixable. The mixture is subjected to thermoplastic forming.

Recycling a fiber-reinforced thermoplastic

A thermoformable, fiber-reinforced composite material contains 5 to 70% by volume of unidirectionally aligned reinforcing fibers having individual filament diameters of 7 to 30 .mu.m, which are bonded by a matrix of a thermoplastic elastomer-modified polypropylene which essentially wets the entire surface of the individual filaments. The elastomer-modified polypropylene preferably consists of a mixture of polypropylene with thermoplastic ethylene-propylene-diene rubber (EPDM) and/or ethylenepropylene rubber (EPM). The reinforcing fibers preferably consist of glass.

Thermoformable, fiber-reinforced composite material, process for its

An apparatus for carrying out membrane separation processes is described. It comprises a housing, at least one spirally wound-up membrane pocket arranged within the housing and containing at least one drainage layer and semipermeable membranes applied to both sides thereof, a spacer between the individual wound plies of the membrane pocket, a centrally arranged collection line, a first end-face opening as an inlet for the material to be separated, a second end-face opening as an outlet for the concentrate and a discharge line for the permeate which has passed into the collection line. The permeate passage from the membrane pocket into the collection line is kept sealed from the space filled with the material to be separated by means of spring-elastic elements, and the semipermeable membranes are mutually joined by energy-bonded seams in the membrane pocket regions adjacent to the side edges. According to the invention no adhesive is required for the apparatus.

Apparatus for carrying out membrane separation processes

A macrophorous, asymmetric, hydrophilic membrane containing polyaramid is described. The characterizing features are that it contains a copolyamide which has at least the following recurring structural units:

Macroporous, asymmetric, hydrophilic polyaramide membrane

Disclosed is the novel compound 4,4'-diphenylether-dialdehyde-bis-dimethylacetyl of the formula ##STR1## and a process for its preparation from di-p-tolyl ether ##STR2## by anodic oxidation of the latter in the presence of methanol and of a supporting electrolyte. The anode material used in this reaction is preferably platinum, lead dioxide, graphite or vitreous carbon, and the cathode material used is preferably steel, nickel, or graphite. The supporting electrolyte used is preferably NaOCH.sub.3, KOH, KPF.sub.6, CsF, NaBF.sub.4, LiBF.sub.4, tetraethylammonium p-toluenesulfonate, H.sub.2 SO.sub.4 or CH.sub.3 OSO.sub.3 H, individually or as a mixture.

4,4'-Diphenyl ether-dialdehyde-bis-dimethylacetal and a process for its

Disclosed is a process for catalytic hydrogenolysis of p-substituted benzaldehyde-dialkyl-acetals of the general formula ##STR1## in which R is an alkyl group, an unsubstituted or substituted aryl group or an unsubstituted or substituted aralkyl group, by means of a catalyst system composed of cobalt carbonyl and at least one nitrogen-containing heterocyclic compound, such as pyridine, pyrrole, pyrrolidone or piperidine and a hydrogen/carbon monoxide mixture to give the corresponding p-substituted benzyl alkyl ether derivatives.

Process for the catalytic hydrogenolysis of p-substituted

4,4'-Diphenyl ether-dialdehyde-bis-dimethylacetal

This invention relates to an improvement in a radiation-sensitive mixture containing (a) a compound which forms an acid under the influence of actinic radiation and (b) a compound which has at least one acid-cleavable C--O--C group and the solubility of which in a liquid developer is increased by the action of an acid, the improvement that the compound which is capable of being cleft by an acid contains at least one enol ether group as the acid-cleavable group. The invention also relates to a process for producing relief images using the radiation-sensitive mixture.

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Mainz, Germany

Detlef H Skaletz