Abstract: The present invention relates to a method for the production of polyamide 6 with low extract content and a device for it. Here, a melt of non-extracted polyamide 6 is cleaned from monomer and oligomers in a degasification device in vacuum, wherein the vapor being withdrawn from the degasification device by the vacuum generation device is cleaned from monomer, oligomers and optionally water at first in a direct condenser which is operated with liquid ?-caprolactam and subsequently in a pre-separator which is cooled with a coolant, before it reaches the vacuum generation device. A particularly preferable variant of the method envisages the usage of the melt of polyamide 6 with low extract content so prepared in a direct process of spinning into textile fibers and/or filaments.

Abstract: The present invention relates to a method for the production of polyamide 6 with low extract content and a device for it. Here, a melt of non-extracted polyamide 6 is cleaned from monomer and oligomers in a degasification device in vacuum, wherein the vapor being withdrawn from the degasification device by the vacuum generation device is cleaned from monomer, oligomers and optionally water at first in a direct condenser which is operated with liquid ?-caprolactam and subsequently in a pre-separator which is cooled with a coolant, before it reaches the vacuum generation device. A particularly preferable variant of the method envisages the usage of the melt of polyamide 6 with low extract content so prepared in a direct process of spinning into textile fibers and/or filaments.

Abstract: A process and a system for producing polyethylene terephthalate (PET) granules by transesterification of dimethyl terephthalate with ethylene glycol or by esterification of (fiber) purified terephthalic acid with ethylene glycol suitable for further processing to form packaging films and bottles, comprising the steps of polycondensation, granulation and latent heat crystallization, aftertreatment of the crude granules to adjust the polymer quality values required for the further processing, in particular the intrinsic viscosity, the acetaldehyde content and the moisture content, wherein the aftertreatment is carried out in multiple moving bed tubular reactors operated in parallel.

Abstract: The invention relates to a method and a device for producing vacuum in the production of polyesters and copolyesters; unrectified vapors from at least one esterification or transesterification stage is preferably used as a driving medium in gas jet pumps for producing the vacuum in one or more polycondensation stages.

Abstract: The invention relates to a method and a device for producing vacuum in the production of polyesters and copolyesters; unrectified vapors from at least one esterification or transesterification stage is preferably used as a driving medium in gas jet pumps for producing the vacuum in one or more polycondensation stages.

Abstract: Process for adjusting the haze value of ethylene terephthalate homopolymers and low-modified copolymers to a value in the range of 0.5 to 20 NTU while they are being produced by direct esterification and polycondensation, where an amount of antimony and germanium catalyst that is determined on the basis of the desired degree of turbidity is added before or at the start of the esterification step in the absence of other catalysts and other compounds that would affect the haze value, and after achieving a conversion of 90 to 98%, another dose of antimony catalyst corresponding to a total added amount of Sb+Ge in the range of 160 to 350 ppm is added, and then after addition of the catalyst is concluded, a phosphorus stabilizer is added to the reaction mixture in an amount to correspond to 0 to 50 ppm phosphorus.