SYNTHESIS OF POLY(2-METHOXY-5-METHYL-1,4-PHENYLENEVINYLENE) AND ITS POLY(1,4-PHENYLENEVINYLENE) COPOLYMERS - ELECTRICAL AND 3RD-ORDER NONLINEAR-OPTICAL PROPERTIES

Asymmetrically disubstituted poly(2-methoxy-5-methyl-1,4-phenyleneviny lene) (PMMPV) and a series of lene-co-2-methoxy-5-methyl-1,4-phenylene vinylene)s (poly(PV-co-MMPV)) were synthesized through a water-soluble precursor route. These polymers were characterized using UV-visible, FT-IR spectroscopy, and a DSC, TGA thermal analyzer. The electrical co nductivities of the polymers were investigated by the four-in-line met hod at room temperature. A PMMPV film can be stretched up to 5 times a nd doped with FeCl3 and I-2 to give electrical conductivities of 27 an d 7.4 S/cm, respectively, along the drawn direction. In copolymers, as the content of the MMPV unit increases, the electrical conductivity s teadily increases. The chi((3)) (-3 omega; omega, omega, omega) value of PMMPV was determined by the third harmonic generation (THG) techniq ue at 1907 nm, the fundamental wavelength. The measured chi((3)) value was 7.5 x 10(-12) esu.