Natriumfluoridhaltige thermoplastische Polyesterformmassen

1,268,155. Polyester moulding compositions. FARBWERKE HOECHST A.G. 1 July, 1970 [1 July, 1969], No. 31874/70. Heading C3R. A thermoplastic moulding composition comprises a mixture of (a) a linear saturated polyester of an aromatic dicarboxylic acid, and, optionally, a small amount of an aliphatic dicarboxylic acid with a saturated aliphatic or cycloaliphatic diol, or of hydroxycarboxylic acid and (b) sodium fluoride having a particle size of less than 10 microns in an amount of from 0.005 to 5% by weight of the polyester. The polyester is preferably polyethylene terephthalate, a polyethylene terephthalate copolyester or polycyclohexane-1,4-dimethylol terephthalate. The composition may also contain talc or boron nitride as additional nucleating agents; salts and ester salts of montan wax, paraffin sulphates and olefin sulphates as mould release agents or copolymers of ethylene and vinyl acetate, ethylene and acrylic acid ester or butadiene and styrene to improve impact strength. Particles of the composition may be coated with waxes, e.g. paraffin wax to keep the moisture content low.