Soluble Aniline-Thiophene Copolymers

Four solvent-soluble poly(aniline-co-thiophene) materials have been prepared by coupling thiophene derivatives with 4-n-butyl aniline using palladium acetate as catalyst. Mn s of up to 17,500 daltons with a PDI of 1.1 were obtained. 

A reactor wrapped with aluminum foil to avoid light penetration was charged with 300 ml of DMF and thiophene (0.5 mol) and then treated with the drop wise addition of V-bromosuccinimide (1.1 mol) and stirred 48 hours in the dark. The mixture was poured into 300 ml of ice-water and stirred for 2 hours until a yellow suspension formed. The suspension was extracted 4 times with 200 ml diethyl ether, and the 

Under continuous nitrogen flow, a reaction flask was dried with a propane torch flame and then cooled to ambient temperature. The flask was charged with 180 ml of toluene, palladium acetate (0.5 mmol), and tri-t-butylphosphine (2.0 mmol) and stirred at ambient temperature until a thick light yellow suspension was obtained. This mixture was then treated with 4-n-butylaniline (10 mmol), the Step 1 product (10 mmol), and sodium t-butoxide (22 mmol) and heated overnight at 80°C. The reaction mixture was poured into 1000 ml of methanol where a brownish precipitation slowly appeared, which was isolated by filtration. The brown solid was dissolved in 50 ml of CCI3H and re-precipitated in 500 ml of methanol, and the product was isolated in 45.0% yield as a brown powder having a M of 7728 daltons with a PDI of 2.12. 

TABLE 1. Physical properties of thiophene and aniUne copolymers. 

Note Limited analytical information supplied by the author. 

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Y. A. Udum, K. Pekmez, A. Yildiz, Electrochemical preparation of a soluble conducting aniline-thiophene copolymer, European Polymer Journal 2005, 41,1136. 

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