Int. J. Surface Science and Engineering, Vol. 11, No. 2, 2017 133 Copyright © 2017 Inderscience Enterprises Ltd. The characterisation of surface treated silica-filled and non-filled polydimethylsiloxane films Michael J. Joyce*, Paul D. Fleming III and Alexandra Pekarovicova Department of Chemical and Paper Engineering, Western Michigan University, USA Email: mjoyce@wmich.edu Email: dan.fleming@wmich.edu Email: a.pekarovicova@wmich.edu *Corresponding author Abstract: In this work, various methods to enable tailoring of polydimethylsiloxane film surfaces are implemented and compared to determine their influence on surface energy and roughness. Films were prepared containing various levels of hydrophilic silica filler. Ultraviolet-ozone, and Piranha solution treatments were also implemented and characterised. Lastly, the combination of both silica filler and treatments were utilised and characterised to understand interactive effects. Influence of filler loading, and surface treatment on roughness, and surface energy of films was determined. Regardless of surface treatment, addition of silica significantly influences total surface energy. Addition of silica influenced total surface energy of the films by itself, and in combination with the Piranha and UV-ozone treatments. The lowest surface energy was that of the control Polydimethylsiloxane film 21.5 N/m. The overall highest surface energy achieved was that of the 10% filled 30-minute Piranha solution treated sample, having a surface energy of 44.1 N/m. Keywords: polydimethylsiloxane; PDMS; surface treatments; UV-ozone; Piranha solution; surface energy; medical devices; wettability; silica-fill; ANOVA; biocompatible. Reference to this paper should be made as follows: Joyce, M.J., Fleming III, P.D. and Pekarovicova, A. (2017) ‘The characterisation of surface treated silica-filled and non-filled polydimethylsiloxane films’, Int. J. Surface Science and Engineering, Vol. 11, No. 2, pp.133–147. Biographical notes: Michael J. Joyce received his BS in Psychology and MS in Paper and Printing Science from Western Michigan University, Kalamazoo MI in 2012 and 2014, respectively. He is currently working as a Teaching Assistant in the Department of Chemical and Paper Engineering while seeking his PhD in Paper and Printing Sciences. He has worked on various client-supported projects for industrial clients through the Center for the Advancement of Printed Electronics and Center for Ink and Printability. He has also served as a Teaching Assistant for courses regarding digital printing processes, ink and colour production, and digital graphics. He has performed projects utilising screen, flexo, gravure and inkjet print methods and has created a novel processing method, enabling the creation of stand-alone printed sensors. His doctoral work is focused on the study of metallic ink interactions with PDMS substrates for creation of biocompatible sensors utilising various printing processes.