1. St Petersburg State University, Universitetskaya nab. 7-9; St Petersburg 199034 Russian Federation
2. Institute of Macromolecular Compounds, Russian Academy of Sciences; Bolshoj pr. 31 St Petersburg 199004 Russian Federation
3. St Petersburg Polytechnic State University; Grazhdansky pr. 28 Saint Petersburg 195220 Russian Federation
4. Materials Engineering Centre, UdR INSTM, NIPLAB; University of Perugia; di Pentima 4 05100 Terni Italy