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Krems an der Donau, Austria

Patent
Metadynea Austria GmbH | Date: 2015-02-27

A method for producing compounds of formula (I) in which the radical R


Himsel A.,Competence Center for Wood Composites and Wood Chemistry | van Herwijnen H.W.G.,Competence Center for Wood Composites and Wood Chemistry | Moser J.,Metadynea Austria GmbH | Kantner W.,Metadynea Austria GmbH | And 3 more authors.
European Journal of Wood and Wood Products | Year: 2016

A previously developed rheometer-based method to examine undesired cold tack (“sticking”) of aminoplastic resins to machinery parts was further modified to enable climate depending measurements. It could be shown that both relative humidity and temperature influence sticking, resulting in a variation in the extent of sticking as well as in the time window of occurrence. The laboratory method has been successfully applied to explain cases of sticking in a particleboard factory. © 2015, Springer-Verlag Berlin Heidelberg. Source


Himsel A.,Competence Center for Wood Composites and Wood Chemistry | Moser J.,Metadynea Austria GmbH | Kantner W.,Metadynea Austria GmbH | Mitter R.,Fritz Egger GmbH and Co. OG | And 3 more authors.
Wood Science and Technology | Year: 2015

Changes in formaldehyde emission guidelines led to changes in the resin formulation. These changes include reduced formaldehyde to urea molar ratio which is followed by a change in reactivity of aminoplastic resins. This resulted in an increased occurrence of an undesired type of tack, herein called “sticking”, which causes addition of resinated wood particles onto machine parts in industrial particle board production. Whereas tack measurements for pressure-sensitive adhesives, such as the probe tack test and rolling ball test exist, mature cold tack tests for liquid formaldehyde-based resins are rare. Practical tests such as “finger-dipping” show limitations in terms of reliability and reproducibility. To measure the sticking behaviour, a rheometer test method is enhanced and modified to quantify influencing factors. The test set-up on a Bohlin CVO rheometer consists of a rotating cylinder which runs over a wood surface coated with resin. The established “glue line” dries out and partially cures, while the torque increases up to a maximum point. This change, caused by “sticking”, is accurately measured and recorded. Influences of different surface temperatures can be observed: the higher the temperature, the faster the drying. In addition, resin age significantly contributed to the sticking effect. Although changes in viscosity are only minor, the torque is highly influenced by resin age, both in measuring time and maximum. Besides temperature and resin age, this method might be useful to describe and investigate further factors influencing sticking issues occurring in the board production process, such as humidity, resin composition, material and surface roughness. © 2015, Springer-Verlag Berlin Heidelberg. Source


Himsel A.,University of Natural Resources and Life Sciences, Vienna | Muller U.,University of Natural Resources and Life Sciences, Vienna | Kantner W.,Metadynea Austria GmbH | Moser J.,Metadynea Austria GmbH | And 2 more authors.
Forest Products Journal | Year: 2015

"Sticking" of glued particles onto machine parts (blender, conveyor, forming station) during wood panel production increasingly occurs when applying low-emission aminoplastic adhesives. Therefore, a new and reproducible method to investigate sticking effects was developed. With this setup, both drying out of the adhesive and the tendency of particles to adhere onto machinery components can be described. The method consists of a rotating cylinder made out of different materials and of diverse surface roughness in order to simulate machine parts, which runs over a wood surface where resin is applied. The wood surface represents the wood particles. The temperature of the wood surface and the ambient air as well as the relative humidity can be controlled. Before starting the experiment, a defined amount of adhesive is applied onto the wood surface and with this a "glue line" is built up. Drying out of the adhesive causes an increase of the rolling resistance up to a peak value. Afterward, an abrupt or gradual decrease of the rolling resistance is observed. This rolling resistance is accurately measured and recorded. Using the approach described above, influences of different materials, climate conditions, surface temperature and roughness, as well as adhesive properties can be observed. The initial results provide strong evidence that climate conditions of the ambient air as well as material and surface properties of machine parts show a significant contribution to the phenomenon. ©Forest Products Society 2015. Source


Mahrdt E.,Competence Center for Wood Composites and Wood Chemistry | Stockel F.,TU Braunschweig | van Herwijnen H.W.G.,Competence Center for Wood Composites and Wood Chemistry | Muller U.,University of Natural Resources and Life Sciences, Vienna | And 3 more authors.
Wood Science and Technology | Year: 2015

A new procedure to detect urea–formaldehyde adhesive in industrial particle board is presented. The method uses thin sections stained with a visible dye (gentian violet) and a fluorescent dye (brilliant sulphaflavine), respectively, in a two-step procedure. Microscope images of a selected area of interest acquired in visible and fluorescence modes are combined to obtain sufficient contrast, enabling semi-automated detection of adhesive by means of image analysis. No addition of dye prior to particle board production is necessary. © 2015, Springer-Verlag Berlin Heidelberg. Source

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