Ralf Frenzel

Generation of Ultrahydrophobic Properties of Aluminium – A first Step to Self‐cleaning Transparently Coated Metal Surfaces

In the last few years, significant efforts have been made to provide surfaces with self-cleaning properties. This approach utilises principles wich have been discovered in nature, like the well known lotus-effect. The transformation of this strategy to metallic surfaces is a scientifically and technologically challenging target. This publication focuses on the investigation of different routes for the generation of the necessary micro-morphological propoerties of Al

Adsorption of Poly(vinylformamide-co-vinylamine) Polymers (PVFA-co-PVAm) on Copper

The adsorption of poly(vinylformamide) (PVFA) and its derivative statistical copolymer poly(vinyl-formamide-co-vinylamine) (PVFA-co-PVAm) on metallic copper and copper oxide particles as well as planar copper surfaces was studied as a function of the degree of hydrolysis of PVFA, the pH, and the polymer concentration in solution. The chemical composition and molecular structure of the PVFA-co-PVAm layers were investigated by surface-sensitive spectroscopic methods such as XPS, DRIFT spectroscopy, and ellipsometry. The findings allowed us to explain the adsorption mechanisms and the forces driving the PVFA-co-PVAm adsorption. It was shown that PVFA-co-PVAm layers thicker than 30 nm are able to protect the planar copper surface against corrosive attack.

Polyelektrolytadsorption ergänzt Laservorbehandlung

Die Festigkeit und Langzeitbeständigkeit geklebter Aluminiumteile hängt bekanntlich sehr stark von der Vorbehandlung der zu klebenden Aluminiumoberflächen ab. Laserverfahren ermöglichen eine lateral definierte Aktivierung von Klebflächen, können aber nicht gewährleisten, dass der erzielte Reinigungsund Aktivierungseffekt bei Lagerung erhalten bleibt. Welche Wirkung zeigen in diesem Kontext geeignete wasserlösliche Funktionspolymere wie zum Beispiel Polyelektrolyte?