Two novel poly(p-phenylene vinylene) polymers, which carried side substituents with cyano groups or 1,3,4-oxadiazole, were synthesized by Heck coupling. They consisted of alternating conjugated segments and nonconjugated aliphatic spacers. The polymers had moderate molecular weights, were amorphous, and dissolved readily in tetrahydrofuran and halogenated organic solvents. They were stable up to approximately 340 degreesC in N-2 and 290 degreesC in air, and the anaerobic char yield was around 60% at 800 degreesC. The polymer with cyano side groups emitted blue light in solutions and thin films with identical photoluminescence (PL) maximum at 450 nm; this supported the idea that chain interactions were hindered even in the solid state. The PL maximum of this polymer in thin films was blueshifted upon annealing at 120 degreesC, indicating a thermochromic effect as a result of conformational changes in the polymer backbone. The polymer containing side substituents with oxadiazole rings emitted blue light in solutions with a PL maximum at 474 run and blue-greenish light in thin films with a PL maximum at 511 nm. The PL quantum yields of the polymers in tetrahydrofuran were 0.13-0.24. (C) 2004 Wiley Periodicals, Inc.