SiCoPC blend containing phosphazene and silicone/acrylate impact modifier

Composition for producing a thermoplastic moulding compound, wherein the composition contains:

• A) 42% to 80% by weight of at least one polymer selected from the group consisting of aromatic polycarbonate and aromatic polyestercarbonate,
• B) 2% to 38% by weight of at least one polysiloxane-polycarbonate block co-condensate characterized in that component B contains siloxane blocks derived from one of the following structures:
• wherein R1 represents hydrogen, Cl, Br, C1-C4-alkyl,
• R2 independently represents aryl or alkyl,
• X represents a single bond, C1 to C5-alkylene, C2 to C5-alkylidene, C5 to C12-cycloalkylidene, —O—, —SO— —CO—, —S—, or —SO2—,
• n is a number between 10 and 150 determined by 1H-NMR spectroscopy,
• m is a number from 1.5 to 5 determined by 1H-NMR spectroscopy,
• C) 1% to 15% by weight of at least one rubber-modified graft polymer comprising
• C.1) 5% to 95% by weight based on the graft polymer C of a shell composed of at least one vinyl monomer and
• C.2) 95% to 5% by weight based on the graft polymer C of a graft substrate composed of silicone-acrylate composite rubber,
• D) 2% to 10% by weight of at least one phosphazene,
• E) 0% to 10% by weight of at least one additive.