A new class of soluble PPV derivatives containing dimethyldodecylsilylphenyl unit as a pendant was synthesized by Gilch polymerization method. The resulting electroluminescent polymers showed good solubility, good film-forming ability onto the ITO substrate, and exhibited an amorphous morphology due to dimethyldodecylsilylphenyl branched group linked to the polymer backbone. The weight average molecular weights and polydispersities of the present EL polymers were in the range of 8.0–80.0 × 104 and 2.67–7.80, respectively. The resulting EL polymers revealed a high thermal stability of up to 355–410°C. Their glass transition temperatures were in the range of 104–251°C. The emission colors could be tuned from green to orange-red colors by changing the MEH-PPV contents in copolymer systems. The turn-on voltages of the EL polymers were in the range of 1.8–4.0 V.