Thermoplastic blends containing polyesters and polyester carbonates based on substituted cycloalkylidene bisphenols

A thermoplastic molding composition comprising a blend of

• A) 1 to 99% by weight of a polyester carbonate derived from
• a) aromatic diphenols,
• b1) at least one member selected from the group consisting of aliphatic acid, cycloaliphatic acid and aromatic dicarboxylic acid, and
• b2) carbonic acid
• wherein said b1) is present in an amount of more than about 0.1 mol-percent and wherein said b2) is present in an amount of up to 99.9 mol-percent, said percent being relative to the total molar amount b1) and b2) and wherein 0.1 to 100 mol-% of said a) consists of diphenols corresponding to ##STR11## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represent a hydrogen atom, a C.sub.1-2 hydrocarbon radical or a halogen atom,
• m is an integer of 4 to 5,
• R.sup.5 and R.sup.6 are individually selected for each X and, independently of one another, represent a hydrogen atom or a C.sub.1-6 alkyl radical and
• X is carbon,
• with the proviso that at least one atom X, R.sup.5 and R.sup.6 are both alkyl radicals, and at least one member selected from the group consisting of
• B) 0 to 99% by weight of an amorphous thermoplastic resin which is different from (A) and which has a glass transition temperature of 40.degree. to 300.degree. C.,
• C) 0 to 99% by weight of a crystalline thermoplastic resin having a melting temperature of 60.degree. to 400.degree. C.,
• D) 0 to 99% by weight of a rubber, and
• E) 0 to 99% by weight of a graff polymer of at least one rubber with at least one grafted-on polymer of at least one monomer from the group consisting of vinyl compounds, acrylic and methacrylic compounds and maleic acid derivatives,
• in which the sum of A), B), C), D) and E) is 100% by weight.