1. Institute of Polymer Chemistry University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
2. Institute of Organic Chemistry University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
3. Chemistry Department Paderborn University Warburger Str. 100 33098 Paderborn Germany
4. German Institutes of Textile and Fiber Research Körschtalstr. 26 73770 Denkendorf Germany