Introducing surface functionality on thermoformed polymeric films

Altres ajuts: this work has been performed within the PLASTFUN project (Planta Pilot de Peces Plàstiques amb Superficies Funcionals Avançades), within the Industries of the Future community (IDF) RIS3CAT, supported by the European Regional Development Fund (ERDF) as part of the operative frame FEDER of Catalonia 2014-2020 EC [COMRDI 16-1-0018], included in the 7th Framework Program. AF, NK and CMST acknowledge support from the CERCA Programme of the Generalitat de Catalunya. We present a fabrication process for the production of 3-dimensional micro-structured polymeric films. The microstructures are fabricated in a single step using thermal nanoimprint lithography as patterning technique. The micro-structured polymer films are then transformed into a 3D shape by means of a plug-assisted thermoforming process, while keeping the functionality of the micro-patterned areas. The preserved functionality is characterized by water contact angle measurements, while the deformation of the micro-structured topographies due to the thermoforming process is analyzed using confocal microscopy and Digital Image Correlation (DIC) techniques. This combined fabrication process represents a promising solution to complement in-mold decoration approaches, enabling the production of new functional surfaces. As the microstructures are fabricated by means of a mechanical modification of the surface, without the need of chemical treatments or coatings, the presented technique represents a promising, simple and green solution, suitable for the industrial fabrication of 3D nonplanar shaped functional surfaces.