Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising thermal postcrosslinking in a contact dryer having external heated outer surfaces.

Abstract: A method for connecting functional elements (14) to a shaft (10, having the following steps: (a) forming elevations (12) for receiving the functional elements (14), said elevations (12) being machined out of the shaft (10) by removing material, and (b) welding the functional elements (14) to the elevations (12) on the shaft (10).

Abstract: The invention relates to a process for operating a mixing kneader, comprising one or more shafts on whose surfaces are disposed kneading bars and which are surrounded by a casing, comprising the following steps: (a) supplying reactants at an addition site in the mixing kneader, (b) converting the reactants in an exothermic reaction, the reaction at first forming a coherent kneadable intermediate, (c) tearing and dividing the coherent kneadable intermediate to form a product, the exothermic reaction optionally continuing during the tearing and division, (d) withdrawing the product at a withdrawal site in the mixing kneader, wherein at least one of the shafts and/or the casing is heated to a temperature above 20° C. during the operation of the mixing kneader.

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising handling water-absorbing polymer particles in intermediate silos, storage silos and/or big bag filing stations that are connected with vent lines having a mitered joint.

Abstract: The invention relates to a process for connecting functional elements (14) to a shaft (10), comprising the following steps: (a) elevations (12) for receiving the functional elements (14) are formed, the elevations (12) being worked out of the shaft (10) by material removal, (b) the functional elements (14) are welded to the elevations (12) on the shaft (10).

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising polymerization, drying the resulting polymer gel on a through circulation belt dryer, crushing the dried polymer gel, pre-grinding, separating of incompletely dried particles with a perforated plate, grinding and classifying the resulting polymer particles.

Abstract: A method for detecting damage to a hollow shaft having no radially encircling notches, openings, or channels by: (a) positioning a sensor for transmitting and receiving a signal at an end face of the hollow shaft, (b) transmitting a signal and receiving an echo of the signal, (c) determining the signal propagation time from the time of transmitting the signal until receiving the echo, (d) comparing the signal propagation time to a predetermined intended value and emitting a warning in the case of a deviation.

Abstract: A method for operating an apparatus with at least one rotating shaft, the at least one rotating shaft comprising functional elements which act on material to be processed in the apparatus, the apparatus comprising a filling orifice and an outlet orifice with an adjustable lower edge, and material being conveyed continuously through the apparatus from the filling orifice to the outlet orifice, said method comprising the following steps: a) measuring load data for the at least one rotating shaft in order to determine shaft load, b) lowering the lower edge of the outlet orifice and/or reducing the quantity of material supplied if the shaft load exceeds a specified maximum load, or displacing the lower edge of the outlet orifice upwards and/or increasing the quantity of material supplied if the shaft load is less than a specified shaft load.

Abstract: The invention relates to a process for operating a mixing kneader, comprising one or more shafts on whose surfaces are disposed kneading bars and which are surrounded by a casing, comprising the following steps: (a) supplying reactants at an addition site in the mixing kneader, (b) converting the reactants in an exothermic reaction, the reaction at first forming a coherent kneadable intermediate, (c) tearing and dividing the coherent kneadable intermediate to form a product, the exothermic reaction optionally continuing during the tearing and division, (d) withdrawing the product at a withdrawal site in the mixing kneader, wherein at least one of the shafts and/or the casing is heated to a temperature above 20° C. during the operation of the mixing kneader.

Abstract: A process for continuous thermal postcrosslinking of water-absorbing polymer particles, wherein the postcrosslinker is applied to the water-absorbing polymer particles by means of suitable nozzles and the nozzles are exchanged or cleaned via the interior of a glovebox adjoining the plant section comprising the nozzle.

Abstract: The invention relates to a method for monitoring the bending of a shaft, particularly a shaft in a mixing kneader, the shaft having a bearing at least on one side. In a first step, the deviation of the shaft from the radial position is measured on at least one position different from the bearing of the shaft. In a further step, a reference value is optionally determined from the measured deviation from the radial position. In a third step, the deviation from the radial position as measured in the first step or the reference value found in the second step is compared with a predetermined limit value.

Abstract: The invention relates to a mixing kneader comprising at least two shafts (2,3) configured as hollow shafts, on whose surfaces kneading bars (4) are disposed on elements (5). The construction of the shafts is selected in such a way that the resonant frequencies of the shafts have a separation of at least 5% from the excitation frequencies. At least one of the shafts is preferably flowed through by a temperature-control medium, the inlet being disposed on one side and the outlet on the other side of the shaft. The mixing kneader preferably comprises at least one orifice above the shafts which is configured as a dome, the dome being closed by a displacer (22). In addition, at least one orifice for product withdrawal is provided, whose orifice cross section is adjustable during operation.

Abstract: A coating process wherein an aqueous liquid is sprayed onto surface postcrosslinked water-absorbing polymer particles in a horizontal mixer and the inner wall of the horizontal mixer which is in contact with the product is made from a stainless steel.

Abstract: The invention relates to a mixing kneader comprising at least two shafts (2,3) configured as hollow shafts, on whose surfaces kneading bars (4) are disposed on elements (5). The construction of the shafts is selected in such a way that the resonant frequencies of the shafts have a separation of at least 5% from the excitation frequencies. At least one of the shafts is preferably flowed through by a temperature-control medium, the inlet being disposed on one side and the outlet on the other side of the shaft. The mixing kneader preferably comprises at least one orifice above the shafts which is configured as a dome, the dome being closed by a displacer (22). In addition, at least one orifice for product withdrawal is provided, whose orifice cross section is adjustable during operation.

Abstract: An application system for applying a solid particle includes an injector housing having a material inlet, a gas inlet, and a material outlet, and an occluder moveably disposed within the injector housing between the gas inlet and the material outlet. The injector housing and the occluder define there between at least one adjustable aperture downstream of the material inlet and in fluid communication with the gas inlet and the material outlet. The aperture has a first open area with the occluder in a first position and a second open area with the occluder in a second position, the second open area being different than the first open area. The system also includes a nozzle having a nozzle inlet coupled to the material outlet and a nozzle outlet, the inlet having a circular cross-section and the outlet having a rectangular cross-section.

Abstract: A process for continuous thermal postcrosslinking of water-absorbing polymer particles, wherein the postcrosslinker is applied to the water-absorbing polymer particles by means of suitable nozzles and the nozzles are exchanged or cleaned via the interior of a glovebox adjoining the plant section comprising the nozzle.

Abstract: The invention relates to a method for monitoring the bending of a shaft, particularly a shaft in a mixing kneader, the shaft having a bearing at least on one side. In a first step, the deviation of the shaft from the radial position is measured on at least one position different from the bearing of the shaft. In a further step, a reference value is optionally determined from the measured deviation from the radial position. In a third step, the deviation from the radial position as measured in the first step or the reference value found in the second step is compared with a predetermined limit value.

Abstract: The invention relates to a mixing kneader comprising at least two shafts (2,3) configured as hollow shafts, on whose surfaces kneading bars (4) are disposed on elements (5). The construction of the shafts is selected in such a way that the resonant frequencies of the shafts have a separation of at least 5% from the excitation frequencies. At least one of the shafts is preferably flowed through by a temperature-control medium, the inlet being disposed on one side and the outlet on the other side of the shaft. The mixing kneader preferably comprises at least one orifice above the shafts which is configured as a dome, the dome being closed by a displacer (22). In addition, at least one orifice for product withdrawal is provided, whose orifice cross section is adjustable during operation.

Abstract: The present invention relates to polymerized hydrogels and processes to make such hydrogels, in particular hydrogel adhesives which are capable of attaching to mammalian skin and can be used in various personal care products, such as waste-management articles, and a variety of functional articles to be worn by a human. The hydrogels described herein are characterized by very low amount of residual starting monomers, impurities, and/or by-products that could be formed during polymerization. Specifically, the hydrogels are made by adding scavengers and/or chain transfer agent prior to polymerization. It has been found, that upon addition of same scavengers the material properties of the polymerized hydrogel differ from the properties of gels polymerized without the scavenger. This is due to the fact, that these specific scavengers act also as chain transfer agents in the radical polymerization.

Abstract: The invention relates to a method of producing discrete patterns of an adhesive coating on a substrate, comprising the following steps: (a) the substrate is moved continuously or discontinuously in a conveying direction, (b) in an application zone a low-viscosity polymerizable and/or crosslinkable precursor material of an adhesive material is applied two-dimensionally to the substrate through at least one opening of substantially slotlike configuration of at least one movable applicator, a pattern being produced by movement of the applicator relative to the substrate, (c) downstream of the application zone the applied precursor material is polymerized and/or crosslinked.