Abstract: A method and a device for the production of polyamide 6 pellets wherein an intermediate drying is not necessary and a combined pelletizing and extraction take place. Depending on the intended use, the pellets may directly be used or subjected to further treatment steps. A device for the production of polyamide 6 pellets includes a melt device for providing a melt of polyamide 6, an underwater pelletizing system which is operable under increased pressure, and a vertical vessel having a cylindrical section and a tapered bottom section. The tapered bottom section is provided with a cooling device and is connected to a pipe comprising a screw and/or a rotary gate valve for conveying pellets. The device includes a circuit for circulating an aqueous solution of ? caprolactam through the underwater pelletizing system and the vertical vessel.

Abstract: The present invention relates to mixtures comprising at least one polyester precursor and at least one alkali- and/or alkaline-earth metal salt where the mixture contains at least one phosphonic acid ester of the Formula (I) (RO)OC—R?—PO(OR)2??(I) where independently R represents a group with 1 to 60 carbon atoms and R? represents a group with 1 to 20 carbon atoms. Furthermore, the present invention relates to the polyester compositions which can be produced from the mixtures and to the resulting polyester films.

Abstract: A method is described for the manufacture of polyesters of aromatic dicarboxylic acids with aliphatic and/or cycloaliphatic dials, in which an aromatic dicarboxylic acid in the presence of a monocarboxylic acid or a mixture of a monocarboxylic acid present in a saturated solution with water or another suitable solvent is converted with an aliphatic or cycloaliphatic dial to a dicarboxylic acid alkanediolestercarboxylate and/or its oligomers, which are polycondensed in further process steps to the polyester.

Abstract: A composition comprising Polytrimethylene terephthalate (PTT) with a reduced emission of acrolein is obtained by contacting Polytrimethylene terephthalate (PTT) resin with an effective amount of a melt stable, organic stabilizing compound. Such PTT resin has an acrolein formation rate at 280° C. of less than 15 ppm/minute. Preferably the residual acrolein content of the PTT resin is less than 10 ppm. The additive organic stabilizing compounds are free from nitrogen atoms. Preferred additive compounds include polyfunctional alkohols, alcoholates, aromatic carboxylic acid anhydrides, carboxylic acids and salts of carboxylic acids. The additive compounds are added to the polymer in molten state and/or to the resin, which is then processed to fibers, filaments, non-wovens, films and/or mouldings.

Abstract: A composition comprising Polytrimethylene terephthalate (PTT) with a reduced emission of acrolein is obtained by contacting Polytrimethylene terephthalate (PTT) resin with an effective amount of a melt unstable, organic nitrogen-containing stabilizing compound. Such PTT resin has an acrolein formation rate at 280° C. of less than 15 ppm/minute. Preferably the residual acrolein content of the PTT resin is less than 5 ppm. Preferred additive compounds include amines, amino acids, amidines, urea and other N-compounds. The additive compounds are added to the polymer in molten state and/or to the resin, which is then processed to fibers, filaments, non-wovens, films and/or moldings.

Abstract: The present invention relates to mixtures comprising at least one polyester precursor and at least one alkali- and/or alkaline-earth metal salt where the mixture contains at least one phosphonic acid ester of the Formula (I) (RO)OC—R?PO(OR)2??(I) where independently R represents a group with 1 to 60 carbon atoms and R? represents a group with 1 to 20 carbon atoms. Furthermore, the present invention relates to the polyester compositions which can be produced from the mixtures and to the resulting polyester films.

Abstract: A method is described for the manufacture of polyesters of aromatic dicarboxylic acids with aliphatic and/or cycloaliphatic dials, in which an aromatic dicarboxylic acid in the presence of a monocarboxylic acid or a mixture of a monocarboxylic acid present in a saturated solution with water or another suitable solvent is converted with an aliphatic or cycloaliphatic dial to a dicarboxylic acid alkanediolestercarboxylate and/or its oligomers, which are polycondensed in further process steps to the polyester.