1. Laboratory of Plastics and Rubber Technology, Department of Physical Chemistry and Materials Science; Budapest University of Technology and Economics; H-1521 Budapest, P.O. Box 91 Hungary
2. Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences; Hungarian Academy of Sciences; H-1525 Budapest, P.O. Box 17 Hungary
3. Clariant Produkte (Deutschland) GmbH; D-81477 München Germany