Polyamide moulding materials for the production of moulded articles having reduced surface carbonization

A moulding material suitable for an extrusion blow moulding process, the moulding material comprising:

• (a) at least one first thermoplastic moulding material comprising a polyamide-6;
• (b) at least one nano-scale filler having an average particle diameter between 500 nm and 10 μm prior to compounding, the nano-scale filler in an amount of 0.5 to 15% by weight of the total weight of the moulding material, wherein the nano-scale fillers are selected from the group consisting of natural and synthetic layered silicates, bentonite, smectite, montmorillonite, saponite, beidellite, nontronite, hectorite, stevensite, vermiculite, illite, pyrosite, kaolin, serpentine, double hydroxides based on silicone, silica, silsesquioxane and combinations thereof;
• (c) at least one fibrous filler material in amounts from about 5 to about 30% by weight of the total weight of the moulding material;
• (d) at least one impact modifier in an amount from about 1% to about 25% by weight of the total weight of the moulding material;
• and
• (e) a second thermoplastic moulding material comprising a polyamide 66,
• wherein a molded article produced from said moulding material has a longer retention of mechanical properties (elongation at break and/or ultimate tensile strength) and a reduced surface carbonization when the moulded article is used at a temperature above 135° C. in comparison with a moulded article comprising the same moulding material that contains no nano-scale fillers.