Abstract: Process for preparing molding materials MM with improved optical and color properties, consisting of a polymer PM which contains units of the formula I in which R1 and R2 are each hydrogen and methyl and R3 is hydrogen, C1-C18-alkyl, C5-C8-cycloalkyl, C6-C10-aryl, C6-C10-aryl-C1-C4-alkyl, where these radicals may be up to trisubstituted by radicals selected from the group consisting of C1-C4-alkoxy and halogen, prepared in an imidation reaction known per se in a reactive extruder, in which, on completion of the imidation reaction, an amount of one or more reducing phosphorus compounds P which is effective for color stabilization is added to the polymer PM, characterized in that the phosphorus compounds are organic phosphorus compounds OP selected from the group consisting of compounds of the formula II in which R4 and R5 are each independently hydrogen or an aromatic 6-membered ring which may be up to pentasubstituted by a C1-C4-alkyl and/or C5-C8-cycloalkyl groups.

Abstract: The invention relates to a method for coloring thermoplastic molding compounds, preferably a polymethyl(meth)acrylate molding compound, using novel aqueous colorant preparations. The invention further relates to a novel water-based colorant preparation.

Abstract: Process for preparing moulding materials MM with improved optical and colour properties, consisting of a polymer PM which contains units of the formula I in which R1 and R2 are each hydrogen and methyl and R3 is hydrogen, C1-C18-alkyl, C5-C8-cycloalkyl, C6-C10-aryl, C6-C10-aryl-C1-C4-alkyl, where these radicals may be up to trisubstituted by radicals selected from the group consisting of C1-C4-alkoxy and halogen, prepared in an imidation reaction known per se in a reactive extruder, in which, on completion of the imidation reaction, an amount of one or more reducing phosphorus compounds P which is effective for colour stabilization is added to the polymer PM, characterized in that the phosphorus compounds are organic phosphorus compounds OP selected from the group consisting of compounds of the formula II in which R4 and R5 are each independently hydrogen or an aromatic 6-membered ring which may be up to pentasubstituted by a C1-C4-alkyl and/or C5-C8-cycloalkyl groups.

Abstract: (EN) The invention concerns a method for producing a thermoplastic molding material or element, said material or element containing nanometric inorganic particles. In molten state, the thermoplastic is mixed with the nanometric inorganic particles and with a solubilizing agent in a conveyor screw extruder, the pressures and temperatures being adjusted so that the plastic is in melt form and the solubilizing agent in supercritical state. The invention is characterized in that at the output of the extruder, the mixture passes through a slot with a passage less than 20 $g(m)m to penetrate into an expansion zone and the molten material, wherein are incorporated the nanometric inorganic particles, is evacuated, reduced into molding material after cooling or transferred into a molding tool to be molded. The invention also concerns the molding material and the molding elements obtained by this method, as well as the uses thereof.

Abstract: (EN) The invention concerns a method for producing a thermoplastic molding material or element, said material or element containing nanometric inorganic particles. In molten state, the thermoplastic is mixed with the nanometric inorganic particles and with a solubilizing agent in a conveyor screw extruder, the pressures and temperatures being adjusted so that the plastic is in melt form and the solubilizing agent in supercritical state. The invention is characterized in that at the output of the extruder, the mixture passes through a slot with a passage less than 20 $g(m)m to penetrate into an expansion zone and the molten material, wherein are incorporated the nanometric inorganic particles, is evacuated, reduced into molding material after cooling or transferred into a molding tool to be molded. The invention also concerns the molding material and the molding elements obtained by this method, as well as the uses thereof.

Abstract: The invention relates to a method for reducing the polymer content in the wastewater from dewatering of two-phase liquid mixtures comprising a thermoplastic plastic melt and an aqueous phase by coagulating the plastic melt and pressing the water out of the melt cake in an extruder system, characterized in that superheated steam with a temperature of at least 280° C. is injected immediately after introduction of the two-phase liquid mixture into the extruder system.

Abstract: The invention relates to a method for reduction of the polymer content in the wastewater from dewatering of two-phase liquid mixtures comprising a thermoplastic plastic melt and an aqueous phase by coagulating the plastic melt and pressing the water out of the melt cake in an extruder system, characterized in that superheated steam with a temperature of at least 280° C. is injected immediately after introduction of the two-phase liquid mixture into the extruder system.