1. Polymers and Pigments Department, National Research Centre, 33 El-Buhouth St., Dokki, Cairo 12622, Egypt
2. Cellulose & Paper Department, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt
3. Institute of Polymers, Composite and Biomaterials, National Research Council of Italy, Mostra d’Oltremare, V.le J.F. Kennedy 54, 80125 Naples, Italy