1. Program in Petrochemistry and Polymer Science; Faculty of Science, Chulalongkorn University; Bangkok 10330 Thailand
2. Bangkok Synthetics Co., Ltd. Muang District; Rayong 21150 Thailand
3. Department of Chemical Technology; Faculty of Science, Chulalongkorn University; Bangkok 10330 Thailand
4. Department of Chemical Engineering; University of Waterloo; Ontario N2L 3G1 Canada