A novel poly(p-phenylene vinylene) (PPV)/poly(p-phenylene ethynylene) (PPE) block-copolymer was synthesized by a cross-coupling polycondensation with Pd(PPh3)(2)CI2 and a phase-transfer catalyst., and was confirmed by H-1 NMR and IR spectroscopy and elemental analysis. The thermal, electrochemical, and photoluminescent properties of the new copolymer have been investigated. The incorporation of triple bonds into the cyano-substituted PPV (CN-PPV) backbone leads to higher oxidation and reduction potentials than poly(2-methoxy-5-(2-ethylhexyloxy)-p-phenylene vinylene) (MEH-PPV) and CN-PPV, potentially making the copolymer a good electron-transporting material for use in a light-emitting-diode device.