1. Post Graduate Department of Chemistry, Bishop Moore College, Mavelikkara, Kerala, India, Leibniz Institute of Polymer Research, Hohe Strasse 6, D-01069 Dresden, Germany, Department of Polymer Chemistry, Chemnitz University, Strasse der Nationen 62, D-09107 Chemnitz, Germany, and School of Chemical Sciences, Mahatma Gandhi University, Priyadarsini Hills P.O, Kottayam, Kerala, India