1. Smart and Sustainable Polymeric Products, Engineering and Technology Institute Groningen, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
2. DPI, P.O. Box 902, Eindhoven 5600 AX, The Netherlands
3. Electron Microscopy, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, Groningen 9747 AG, The Netherlands