1. Contribution from the Institut für Polymerforschung Dresden, Hohe Strasse 6, 01069 Dresden, Germany, Department of Water Born Polymers, Fraunhofer-Institut für Angewandte Polymerforschung, Geiselbergstrasse 69, 14476 Golm, Germany, and Institute of Macromolecular Chemistry, Heyrovsky Sq. 2, 162 06 Praha 6 − Brevnov, Czech Republic