1. Center of Radiation Processing for Polymer Modification and Nanotechnology (CRPN), Faculty of Science, Kasetsart University, 50 Ngamwongwan Road, Lat Yao, Chatuchak, Bangkok10900, Thailand
2. Department of Materials Science, Faculty of Science, Kasetsart University, 50 Ngamwongwan Road, Lat Yao, Chatuchak, Bangkok10900, Thailand