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Verfahren zur Modifizierung der Oberflaeche von Partikeln und hierzu geeignete Vorrichtung

Cyclic process for modifying surface of particles in relaxing atmospheric pressure plasma, comprises providing particles with a cover that consists of a component that is fluid at room temperature and atmospheric pressure
 
: Ihde, J.; Lommatzsch, U.; Kolacyak, D.; Degenhardt, J.

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Frontpage ()

DE 102009000259 A: 20090115
DE 102009000259 A: 20090115
B05D0007
C23C0016
Deutsch
Patent, Elektronische Publikation
Fraunhofer IFAM ()

Abstract
(A1) Die vorliegende Erfindung betrifft ein Verfahren zur Modifizierung, beispielsweise Funktionalisierung, der Oberflaeche von Partikeln, insbesondere Mikro- und Nanopartikeln, in einem Atmosphaerendruckplasma. Bei dem Verfahren werden die zu modifizierenden Partikel mit einer Huelle versehen, die aus mindestens einer Verbindung besteht, die bei Raumtemperatur und Atmosphaerendruck fluessig ist, und die umhuellten Partikel werden einem Atmosphaerendruckplasma ausgesetzt, in dem ihre Oberflaeche modifiziert wird. Das erfindungsgemaesse Verfahren kann leicht als zyklischer Prozess gestaltet werden, der eine bevorzugte Ausfuehrungsform der Erfindung ist. Gemaess einem weiteren Aspekt betrifft die Erfindung eine Vorrichtung, die fuer die Durchfuehrung des erfindungsgemaessen Verfahrens besonders geeignet ist. Das erfindungsgemaesse Verfahren kann besonders einfach in bestehende Produktionsanlagen integriert werden. Darueber hinaus ist es kostenguenstig und erlaubt die gezielte Veraenderung von Eigenschaften der Partikel durch Modifizierung ihrer Oberflaeche.

 

DE 102009000259 A1 UPAB: 20100802 NOVELTY - The cyclic process comprises providing particles (1) with a cover that consists of a component (2) that is fluid at room temperature and atmospheric pressure, and exposing the covered particles to atmospheric pressure plasma (3) in which the surface of the particle is modified. The particles have a grain size of greater than or equal to 1 mm. The dimension of the particle lies in a dimension in nanometer range. The component is water or alcohol. The covered particles are transported with a carrier gas to the atmospheric pressure plasma. The particles are provided with the cover of the component. DETAILED DESCRIPTION - The cyclic process comprises providing particles (1) with a cover that consists of a component (2) that is fluid at room temperature and atmospheric pressure, and exposing the covered particles to atmospheric pressure plasma (3) in which the surface of the particle is modified. The particles have a grain size of greater than or equal to 1 mm. The dimension of the particle lies in a dimension in nanometer range. The component is water or alcohol. The covered particles are transported with a carrier gas to the atmospheric pressure plasma. The particles are provided with the cover of the component so that it is dispersed in the connection and the dispersion is sprayed through a jet pump (4) under formation of the covered particles. The dispersion of the particles is carried out in the component under effect of ultrasound and/or through the supply of surfactants. The covered particles in a reaction chamber (5) are exposed to atmospheric pressure plasma, which is produced through a plasma nozzle. The stimulation for the atmospheric pressure plasma is pulsed. The atmospheric pressure plasma is produced with process gas. A coating precursor compound is fed into the atmospheric pressure plasma. The surface modified particles are subsequently separated from non-surface modified particles. The different sedimentation speed of the surface-modified and the non-surface modified particles is carried out in a sedimentation fluid. The sedimentation speed of the non-surface modified particle in the sedimentation fluid is larger than the surface-modified particle. The sedimentation speed and the components are identical for covering the particles. The surface-modified particles in the sedimentation fluid carry a reaction with reactants that are contained in the sedimentation fluid. The particles are dispersed in a dispersion container in a solvent, which is fluid at room temperature and atmospheric pressure. The dispersion of the particle is atomized through a jet pump that is operated with a carrier gas under formation of the covered particle. The covered particles are transported in a reaction volume produced through atmospheric pressure plasma in which its surface is modified. The surface modified particles are transported together with non-surface modified particles in a sedimentation container. The sedimentation container has an upper flow and lower flow that contains a solvent as sedimentation solvent and in which the non-surface modified particle falls as the surface-modified particles based on its high sedimentation speed. The surface-modified particles are taken through the upper outlet from the sedimentation container and the non-surface modified particles are led back together with the solvent over the lower flow of the sedimentation container. The transportation of the covered particles, the surface-modified particles and the non-surface modified particles are carried out primarily through the carrier gas. The carrier gas is fed after conducting through the sedimentation solvent for cleaning through a cyclone. An INDEPENDENT CLAIM is included for a device for modifying surface of particles in atmospheric pressure plasma. USE - Cyclic process useful for modifying surface of particles in atmospheric pressure plasma. ADVANTAGE - The cyclic process ensures simple and economical modification of the surface of particles in atmospheric pressure plasma with high quality.

: http://publica.fraunhofer.de/dokumente/N-139538.html