1. Deparamento de Engenharia Quimica, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal, Max Plank Institute of Colloids and Interfaces, Am Mühlenberg 1, 14424 Golm/Potsdam, Germany, and Fraunhofer Institute for Applied Polymer Research, Geiselbergstrasse 69, 14476 Golm, Germany