Kodithuwakku, U.Prashantha, M.A.B.Ratnaweera, D.R.2025-11-042025-11-042016-11-05Proceedings of the Peradeniya University International Research Sessions (iPURSE) – 2016, University of Peradeniya, P 320978-955-589-225-4https://ir.lib.pdn.ac.lk/handle/20.500.14444/5960Polythiophene and its derivatives have become more desirable due to their applications in various fields. These applications arise due to their inherent properties, such as optical and electronic conductive properties; as well as thermal and environmental stability. Precursors of polythiophenes are generally obtained from petroleum by-products, which are non-renewable. It has been reported that precursors of polythiophenes and its derivatives are naturally available in different types of Tagetes species such as Tagetes erecta, Tagetes tenuifolia, etc. A number of thiophene derivatives such as 2, 2’:5’, 2’’-terthienyl (Alpha-T), 5- (3-buten-1-ynyl)-2, 20-bithienyl (BBT), 5-(4-hydroxy-1-butynyl)-2, 20-bithienyl (BBTOH), and 5-(4-acetoxy-1-butynyl)-2, 20-bithienyl (BBTOAc), were found and identified, specifically in the roots of Tagetes species. The current study reports the polymerization of the extracted thiophene derivatives from Tagetes erecta and 3-hexylthiophene (3HT) to obtain a random copolymer of poly (thiophenes-3-hexylthiophene). The extracted thiophene derivatives were partially purified and characterized. The mixture of plant based thiophenes and commercial 3HT with various weight compositions were selectively polymerized on the direct one-step chemical oxidative free radical polymerization to obtain co-polymers. Structural characterization of the synthetic products was done using Fourier Transformation Infrared, Proton Nuclear Magnetic Resonance, Ultra Violet Visible and X-ray Diffraction techniques. Homopolymers of polythiophene obtained from plant based thiophenes have limited processability of solar cells due to poor solubility in common organic solvents. 'However, a significant progress of the solubility was observed with copolymers having partial contribution of 3HT.en-USPolythiophenePlant based thiopheneOrganic solventsArticle