Multilayer tubular sheet based on polyamide, process of its preparation and use

摘要

A multi-layered polyamide-based tubular film has: (a) an outer layer based on an aliphatic or partly-aromatic (co)polyamide; (b) an intermediate layer based on ethylene/1-8C alkyl acrylate copolymers and ethylene/1-8C alkyl acrylate/maleic anhydride copolymers; and (c) an inner layer comprising aliphatic or partly-aromatic (co)polyamides (40-100 wt.%), carboxyl group-containing ethylene copolymers or salts (0-60 wt.%) and further polymers (0-20 wt.%) A multi-layered polyamide-based tubular film has: (1) an outer layer based on an aliphatic or partly-aromatic (co)polyamide which can be up to 30 wt.% replaced by other polymers; (2) an intermediate layer based on ethylene/1-8C alkyl acrylate copolymers and ethylene/1-8C alkyl acrylate/maleic anhydride copolymers which can be up to 20 wt.% replaced by other polymers; and (3) an inner layer comprising aliphatic or partly-aromatic (co)polyamides (40-100 wt.%), carboxyl group-containing ethylene copolymers or salts (0-60 wt.%) and further polymers (0-20 wt.%), the total of these being 100 wt.%.