MONOAXIALLY STRETCHED SHAPED ARTICLE OF POLYTETRAFLUOROETHYLENE

• Main Authors: ADALBERT GEORG WIMMER, FRANZ SASSHOFER, CHRISTIAN H.F. SCHLOSSNIKL, REINHARD REINMUELLER
• Format: Patent
• Language: English
• Published: 28.12.1990
• Edition: 5
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; CHEMISTRY; COMPOSITIONS BASED THEREON; CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, ORYARNS; FINISHING OR DRESSING OF FILAMENTS, YARNS, THREADS, CORDS,ROPES OR THE LIKE; GENERAL PROCESSES OF COMPOUNDING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; MECHANICAL FINISHING OF YARNS OR ROPES; METALLURGY; NATURAL OR ARTIFICIAL THREADS OR FIBRES; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; SPINNING; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WARPING OR BEAMING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP; YARNS; YARNS OR THREADS

For the production of a monoaxially stretched shaped article of polytetrafluoroethylene (PTFE), a pasty composition containing PTFE powder is worked continuously into a moulding, which is passed over a plurality of rollers or rolls, is heated and stretched, the moulding being heated before applying the stretching tension to a temperature of between 327 and 450 DEG C, preferably between 350 and 390 DEG C, is thereby sintered and then stretched. This process allows the production of a monoaxially stretched shaped article of polytetrafluoroethylene (PTFE) having strength values in the direction of stretching of at least 500 N/mm , preferably at least 700 N/mm , and a density of between 1.80 and 2.30 g/cm .