Adhesion-adapted polymer coating systems as filmic model systems for homogeneous geometry-independent surface coating for cleaning analyses

In industrial parts cleaning and metal processing, there are currently no filmic model soiling’s that make it possible to generate homogeneous soiling films independent of geometry. However, this is essential for defined and reproducible cleaning tests. Polymer based coatings can close this gap. In the work presented here, a suitable optimised copolymer with carboxy groups as adhesive groups was developed and investigated for this application purpose. The polymer's cleaning behaviour, and therefore its adhesion, is adapted to that of a reference soiling. A fluorescent dye was attached to the polymer for subsequent detection and a dipping process was developed for the defined application of the copolymer. Comprehensive layer characterisation and systematic cleaning tests using ultrasound proved the reproducibility and uniformity of the generated layers. The residual layers of the polymer after each cleaning step could be quantified both by means of ellipsometry on smooth substrates and by measuring the fluorescence intensity. The process was extended to complex three-dimensional geometries and tested on cleaning systems in an industrial environment in order to validate the applicability, practicability, and efficiency of the developed method. The results show that the selected polymer concept provides a promising solution for the production of a uniform model soiling in component cleaning.