A solid state oxidative polymerization process for the synthesis of conjugated polymers comprising mixing monomer selected from group of compounds of formula I, II, III, IV and V with an oxidizing agent selected from at least one ferric salts such as ferric chloride, ferric tosylate, bromine, sodium peroxy-disulphate and/or ammonium peroxydisulphate, wherein the polymerization is carried out in the absence of solvent.