Abstract: The present invention relates to a polyoxymethylene molding composition comprising (A) 0.1-5.0% by weight of colorant, (B) 0.01-0.5% by weight of a nitrogen-containing stabilizer, (C) 0.05-1% by weight of an ester of a polyhydric alcohol and at least one fatty acid, and (D) 0.001-0.5% by weight of a metal salt of a fatty acid, and (I) polyoxymethylene polymer and, where appropriate, up to 40% by weight of other conventional additives, and variants of this constitution in advantageous versions. In the case of these polyoxymethylene molding compositions the selection of the colorants is no longer restricted to conventional colorants suitable particularly for POM. The products produced therewith are particularly stable during processing and feature low formaldehyde emission, defect-free surfaces, and high color fastness.

Abstract: The present invention relates to a polyoxymethylene molding composition comprising (A) 0.1-5.0% by weight of colorant, (B) 0.01-0.5% by weight of a nitrogen-containing stabilizer, (C) 0.05-1% by weight of an ester of a polyhydric alcohol and at least one fatty acid, and (D) 0.001-0.5% by weight of a metal salt of a fatty acid, and (I) polyoxymethylene polymer and, where appropriate, up to 40% by weight of other conventional additives, and variants of this constitution in advantageous versions. In the case of these polyoxymethylene molding compositions the selection of the colorants is no longer restricted to conventional colorants suitable particularly for POM. The products produced therewith are particularly stable during processing and feature low formaldehyde emission, defect-free surfaces, and high color fastness.

Abstract: The use of polyarylene sulfides or liquid-crystalline polyesters is described in cooling devices for electrical equipment. The use of these polymers can ensure that the electrical conductivity of insulating coolant fluids remains low in continuous operation. Fuel cells are particularly suitable electrical equipment.

Abstract: Molding compositions made from linear polyoxymethylene copolymers which essentially have oxymethylene units and oxyethylene units as structural units in the polymer chain, where the proportion of oxyethylene units in the structural units of the polymer chain is from 1.5 to 2.5 mol %. These molding compositions, and also uncolored or colored moldings produced from these have high stability and extremely low emission of formaldehyde and of residual monomers. At the same time they have a high level of mechanical properties, and they can therefore be utilized without restriction for the customary application sectors and processing methods.

Abstract: The present invention relates to a polyoxymethylene molding composition comprising

Abstract: A process for the continuous preparation of a thermoplastic molding composition with narrow scatter of the melt flow index, which comprises mixing two or more chemically identical starting materials of different melt flow index in a pelletizing extruder fitted with an on-line melt flow index meter and adjustable metering systems.

Abstract: Colorant concentrates made from free-flowing polyoxymethylene copolymer as carrier, 15-80% by weight of colorant, 2-15% by weight of nitrogen-containing stabilizer and 0-15% by weight of dispersion aid for coloring pellets or molding compositions made from polyoxymethylene (POM) and for producing colored injection moldings or colored POM extrudates. The products produced with this colorant preparation are particularly stable during processing and have very low formaldehyde emissions.

Abstract: The novel molding made from a combination of polyacetal with directly molded-on function elements is distinguished by the fact that the function elements comprise one or more elastomers. Such elastomers comprise partially or fully hydrogenated nitrile rubbers, one- or multicomponent silicone rubbers or sulfur-containing rubbers.

Abstract: The novel molding made from a combination of polyacetal with directly molded-on function elements is distinguished by the fact that the function elements comprise one or more elastomers. Such elastomers comprise partially or fully hydrogenated nitrile rubbers, one- or multi-component silicone rubbers or sulfur-containing rubbers.

Abstract: The novel molding made from a combination of polyacetal with directly molded-on function elements is distinguished by the fact that the function elements comprise one or more elastomers. Such elastomers comprise partially or fully hydrogenated nitrile rubbers, one- or multi-component silicone rubbers or sulfur-containing rubbers.

Abstract: A continuous process for the preparation of polyacetal copolymers from 1,3,5-trioxane and the comonomers known for this purpose using strong protic acids as an initiator, in which the initiator is added in an amount of 0.01 to 0.6 ppm, based on the total amount of monomers, in finely divided form to the monomer mixture, after the polymerization step the crude polymer is transferred from the polymerization reactor to a mixing unit without further intermediate steps, excess monomer is removed from the crude polymer in the mixing unit or between polymerization reactor and mixing unit by applying reduced pressure and, if desired, generally customary stabilizers, assistants, fillers, reinforcing materials and/or colorants are incorporated into the polymer in the mixing unit.

Abstract: A moulding composition based on linear polyoxymethylene copolymers and customary additives with a melt index MFI (2,16 kg, 190.degree. C.) of .ltoreq.0,8, preferably .ltoreq.0,5 and especially .ltoreq.0,2 g/10 min has an extraordinary high toughness, which eliminates an addition of elastomer modifiers. In its preparation Lewis acids or protonic acids are used as initiators.

Abstract: A process for efficiently producing a hollow molding or a sheet- or rod-shaped molding includes subjecting a composition containing a polyoxymethylene copolymer resin having substantially a linear molecular structure and a melt flow index (MI) value (190.degree. C., 2160 g load) of 0.1 to 2.0 g/10 min to blow -molding or extrusion-molding operations. The preferred polyoxymethylene copolymer is prepared by copolymerizing trioxane as the principle monomer with a cyclic ether or cyclic formal comonomer in the presence of 1.times.10.sup.-3 to 1.times.10.sup.-2 molar % of a boron trifluoride catalyst or a coordination compound thereof, while regulating the chain-terminating or chain-transferring impurities in the reaction system to 1.times.10.sup.-2 molar % or less, and then cooling the product obtained to a temperature of 45.degree. or below within 30 seconds so as to deactivate the catalyst.

Abstract: Processes for producing a polyoxymethylene copolymer includes forming a crude polyoxymethylene copolymer by subjecting a reaction system containing trioxane, a cyclic ether or cyclic formal comonomer, and a catalyst (e.g., boron trifluoride or a coordination compound thereof) to copolymerization reaction conditions. During copolymerization, both the total content of impurities and catalyst in the copolymerization reaction system are adjusted. In this regard, the impurities content (i.e., those compounds which form unstable end groups in the polyoxymethylene copolymer and/or those compounds having a chain-terminating or chain-transfer function) in the copolymerization reaction system is adjusted to 1.times.10.sup.-2 mole percent or less based on the total monomer amount, while the the content of the catalyst in the copolymerization reaction system to between 1.times.10.sup.-3 to 1.times.10.sup.-2 mole percent based on the total monomer amount.