COATED PIPES HAVING IMPROVED MECHANICAL PROPERTIES AT ELEVATED TEMPERATURES AND A METHOD OF PRODUCTION THEREOF

• Main Authors: Fredriksen, Siw Bodil, Bentzrod, Pal Christian, Vahteri, Markku, Leiden, Leif, Anker, Martin, Rekonen, Petri, Bäckman, Mats
• Format: Patent
• Language: English; French; German
• Published: 03.06.2020
• Subjects: ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF MATERIALS THEREFOR; WOODSTAINS

The present invention deals with coated pipes having a layer of multimodal polyethylene. The multimodal ethylene copolymer is a copolymer of ethylene with one or more alpha-olefin comonomers having from 4 to 10 carbon atoms and has a weight average molecular weight of from 70000 g/mol to 250000 g/mol and a melt index MFR 2 of from 0.05 g/10 min to 5 g/10 min, a melt index MFR 5 of from 0.5 to 10 g/10 min and a density of from 945 kg/m 3 to 958 kg/m 3 . The coatings have a high stiffness, good properties at elevated temperatures and acceptable stress-cracking properties.