1. 1Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt.
2. 2Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt
3. 3Laboratory of Advanced Polymers & Optimized Materials (LAPOM), Department of Materials Science and Engineering, University of North Texas, POBox 305310, Denton, TX 76203-5310, USA.
4. 4Chemistry Department, Faculty of Science, Ain Shams University, Abassia, Cairo, Egypt.