Electrical and optical properties of polyacetylene copolymers

Poly(phenyl vinyl sulfoxide) (PVSO) is a soluble precursor to polyacetylene (PA). Upon thermal elimination, the thermally labile PVSO can be converted to PA by undergoing a 'zipper-like' 5-members cyclic sigmatropic elimination process. Both PVSO and its copolymers can be synthesized via anionic polymerization in which stereospecific polymers with controlled molecular weight, narrow polydispersity, and known chemical composition distribution can be prepared. The degree of elimination and thus the mean conjugation length can be controlled by partially oxidizing the thermally labile sulfoxide moieties into thermally stable sulfone moieties. The optical properties of the PVSO copolymers in the UV-vis range were studied as a function of its thermolysis conditions both in solid-state and in solution forms. The eliminated PVSO can be doped (by p- or n-type dopants) to achieve conductivity to a range of 10 S/cm. The electrical properties of the PVSO copolymers and a series of blends were analyzed as a function of its chemical composition. In addition, the anionic synthesis method allows specific end groups to be inserted to the polymer chain ends. The synthesis of a series of carboxylic acid terminated PVSO polymers and their properties was also reported.