| abstract |
A THERMOPLASTIC RESIN SHAPED ARTICLE HAVING A DOUBLE LAYERED WALL STRUCTURE IS PROVIDED WHEREIN BOTH LAYERS ARE STRONGLY BONDED TO EACH OTHER. ONE LAYER THEREOF COMPRISES A MIXTURE OF (A) 30 TO 95% BY WEIGHT OF C-2 OR -3 OLEFIN HOMOPOLYMER OR COPOLYMER OR A BLEND THEREOF AND (B) 70 TO 5% BY WEIGHT OF AN ETHYLENE COPOLYMER CONTAINING 0.1 TO 10% BY MOLE OF A ZINC SALT OF METHACRYLIC ACID, AND THE OTHER LAYER COMPRISES POLYAMIDE. THE SHAPED ARTICLE IS PREPARED BY THE STEPS OF SEPARATELY MELTING BOTH LAYER COMPONENTS AND THEN, JOINING BOTH THE MELTS UNDER A PRESSURE INSIDE A DIE OF AN EXTRUDER BEFORE THE MELTS ARE SOLIDIFIED AND EXTRUDING SAID MELTS AS A DOUBLE LAYERED TUBULAR ARTICLE. THE SHAPED ARTICLE HAS AN IMPROVED RESISTANCE TO THE TRANSMISSION OF VARIOUS CHEMICALS, GASOLINE, WATER VAPOUR, ETC. |