Poly[(2-(2-phenylethenyl)-1,4-phenylene)vinylene] (PPEPV), poly[(2-methoxy-5-(2-phenylethenyl)-1,4-phenylene)vinylene] (PMPEPV), and their copolymers containing 1,4-phenylenevinylene (PV) units [poly(PEPV-co-PV)s and poly(MPEPV-co-PV)s] were synthesized via water soluble, polyelectrolyte precursor polymers. Electronic spectral characteristics of the polymers clearly demonstrate that the cross-conjugation between the main chain and the pendant 2-phenylethenyl(beta-styryl) unit is insignificant. Electrical conductivities of FeCl3-doped PPEPV and PMPEPV were on the order of 10(-4) S cm-1, which were lower than those of copolymers containing PV units. This is ascribed to the charge-transfer interactions between the dopants and styryl units in the side branch. The MPEPV copolymer containing about 93 mol % of PV unit, however, exhibited an electrical conductivity of about 5 S cm-1, when it was doped with FeCl3. The PEPV copolymer containing 85 mol % PV unit showed an electrical conductivity (0.24 S cm-1) of 1 order of magnitude lower. In general, doping with I2 resulted in lower electrical conductivities than doping with FeCl3.