TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compound: The basic compound is metal hydride, metal alkoxide, metal hydroxide, metal amide, metal amine, organometal compound of alkali or alkaline-earth metal, Grignard reagent, ammonium hydroxide, pyridine, or phosphazene base. The amount of basic compound is 1-2 equivalent with respect to the monomer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The basic compound is metal hydride, metal alkoxide, metal hydroxide, metal amide, metal amine, organometal compound of alkali or alkaline-earth metal, Grignard reagent, ammonium hydroxide, pyridine, or phosphazene base. The amount of basic compound is 1-2 equivalent with respect to the monomer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Solvent: The organic solvent is an aprotic solvent.    TECHNOLOGY FOCUS - POLYMERS - Preparation (claimed): The polymer precursor compound is prepared by reacting a monomer of formula (I) with a basic compound comprising groups R 3 and R 4, in the presence of an organic solvent.Ar,R 1-R 4=as mentioned above.Preferred Conditions: The concentration of monomer is 0.1-0.3M. The reaction of monomer with basic compound is carried out at -78 degrees C to 200 degrees C, preferably -20 degrees C to 30 degrees C. The thermal conversion step is carried out under inert atmosphere. The polymer precursor is dissolved in a solvent followed by a degassing step. Preferred Polymer: The conjugated arylene vinylene polymer, which is a linear polymer, is poly(2,5-thienylene vinylene). Preferred Properties: The polymer precursor compound is in the form of a thin film polymer precursor layer. The polymer precursor compound has an average molecular weight of 5000-500000 Daltons, and a polydispersity of 1.5-5.5, preferably less than 2. Preferred Definitions:    Ar=4-20C aromatic divalent group optionally substituted with substituent(s) chosen from 1-20C alkyl, 3-20C alkoxy, 1-20C alkylsulfate, phenyl, and benzyl, and which may comprise up to 4 heteroatoms chosen from oxygen, sulfur and nitrogen in the aromatic divalent group, preferably 1,4-phenylene, 2,6-naphthalenediyl, 1,4-naphthalenediyl, 1,4-anthracenediyl, 2,6-anthracenediyl, 9,10-anthracenediyl, 2,5-thienylene, 2,5-furanediyl, 2,5-pyrrolediyl, 1,3,4-oxadiazole-2,5-diyl, 1,3,4-thiadiazole-2,5-diyl, 2,5-benzo(c)thienylene, thieno(3,2-b)thiophene-2,5-diyl, pyrrolo(3,2-b)pyrrole-2,5-diyl, pyrene-2,7-diyl, 4,5,9,10-tetrahydropyrene-2,7-diyl, 4,4'-biphenylene, phenanthrene-2,7-diyl, 9,10-dihydrophenanthrene-2,7-diyl, dibenzofurane-2,7-diyl, dibenzofurane-2,7-diyl, and/or dibenzothiophene-2,7-diyl, more preferably 2,5-thienylene;    R 1,R 2=methyl, ethyl or isopropyl;and    R 3,R 4=H.    EXAMPLE - To acetonitrile/water solution (50 mol) (5 vol.% water) of 1,4-bis(tetrahydrothiopheniomethyl) xylene dichloride (6 g), diethyldithiocarbamic acid sodium salt trihydrate (8.87 g) was added as a solid, after which the mixture was stirred at ambient temperature for 2 hours. Then, water was added and the desired monomer was extracted with ether and dried over magnesium sulfate. Evaporation of the solvent yielded 90% of the pure product (p-xylylene bis(N,N-diethyl dithiocarbamate) (6.2 g) as a white solid. A solution of the synthesized monomer (500 mg) in dry tetrahydrofuran (THF) (6.25 ml) at -78 degrees C (or room temperature or 0 degrees C) was degassed for 1 hour by passing through a continuous nitrogen flow. The mixture was then kept at -78 degrees C (or room temperature or 0 degrees C) for 90 minutes while the passing of nitrogen was continued. After this, the solution was allowed to come to 0 degrees C or ethanol (6 ml) was added at -78 degrees C to stop the reaction. The polymer was then precipitated in ice water (100 ml) and extracted with chloroform. The solvent of the combined organic layers was evaporated under reduced pressure and second precipitation was carried out in a 1/1 mixture (100 ml) of diethyl ether and hexane at 0 degrees C. The polymer was collected and dried in vacuum. The residual fractions only contained monomer residues. Polymerization experiment was carried out at -78 degrees C. The obtained conjugated polymer had a molecular weight of 7300 g/mol and a polydispersity of 1.5.