DE1544895

• Main Authors: MEYER, KARL-HEINRICH, HECHELHAMMER, WILHELM, STREIB, HUGO, DR, MICHAEL, DIETRICH
• Format: Patent
• Language: English
• Published: 04.07.1974
• Edition: 1
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

Compositions of polycarbonate resins and glass fibres are treated, prior to or after moulding to give the moulded composition a density which is above 98% of the theoretical density. This may be effected (a) by pressing injection moulded or extruded sheets of the composition in a sheet press or between pressure rollers, preferably at an elevated temperature but below the melting point of the polycarbonate; or (b) by subjecting a molten mixture of the polycarbonate and glass fibres in a worm-extruder to a vacuum to remove volatiles and then extruding the composition either into shaped articles or into strands which are chopped up for further working up by injection moulding or extrusion. The glass fibres are preferably pre-sized with polycarbonates. The compositions may also contain glass powder, quartz, graphite, molybdenum disulphide, powdered tetrafluoroethylene, metal powder or threads, or fibres of cotton, sisal, asbestos or synthetics. In the examples, the polycarbonate used is that of bisphenol A. Uses.-Manufacture of sheets, foils, strips, profiles, venetian blinds, dental prostheses, fishing tackle, electrical components, containers, coated wires.