Soluble poly(3-hexyl-2

5-thienylene vinylene) (PHTV) was readily synthesized from thiophene in a yield better than that of the precursor method to prepare poly(thienylene vinylene) (PTV). The bandgap of the polymer is about 1.8 eV

which is comparable with that of PTV. Owing to the introduction of alkyl side groups onto the backbone of the polymer

it can be dissolved in common organic solvents such as chloroform

THF and toluene. The synthesis of soluble PHTV is a very important approach to preventing oxidation and to improving the properties and the processbility of the PTV. The existence of alkyl side groups in PHTV does not affect its

bandgap and thermal properties as compared with PTV. After doping with FeCl3

the conductivity of PHTV is as high as 1.1 10-2S/cm. The soluble PHTV can be easily transformed into thin film with much better quality than that of the PTV film prepared by the traditional precursor method

which is very important for fabricating devices with good properties.