1. Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
2. Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
3. German Institutes of Textile and Fiber Research (DITF) Denkendorf, Körschtalstrasse 26, D-73770 Denkendorf, Germany