TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compounds: The alkaline environment is provided by sodium carbonate aqueous solution.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compounds: The catalyst is tetrakis(triphenylphosphine)palladium. The solvent is toluene. Preferred Method: Compound (II) is obtained by adding n-butyl lithium to tetrahydrofuran solution of dibromo-alkenyl-fluorene derivative of formula (IV) such that the molar ratio of n-butyl lithium and compound (IV) is 2-4:1, in anhydrous anaerobic environment, stirring at -70 degrees C to -85 degrees C for 0.5-4 hours, adding 2-isopropoxy-4,4,5,5-tetramethyl-(1,3,2)dioxaborolane at the same temperature such that the molar ratio of n-butyl lithium and 2-isopropoxy-4,4,5,5-tetramethyl-(1,3,2)dioxaborolane is 1:1-2, warming the reaction mixture to room temperature for 10-48 hours, washing the resulting solution with saturated sodium chloride, extracting with chloroform or toluene, drying the organic phase obtained by removing the collected water, filtering, collecting filtrate, rotary-evaporating the filtrate to remove excess solvent, and separating the obtained crude product by column chromatography over alumina to obtain purified compound (II). Compound (IV) is obtained adding alkyl magnesium bromide in diethyl ether to tetrahydrofuran solution of 9-(bis-methylsulfanyl-methylene)-2,7-dibromo-9H-fluorene at -5 degrees C in anaerobic environment, such that the molar ratio of alkyl magnesium bromide and 9-(bis-methylsulfanyl-methylene)-2,7-dibromo-9H-fluorene is 2-2.4:1, reacting for 30 minutes or more at 0 degrees C, adding tetrahydrofuran solution of lithium tetrachlorocuprate such that the molar ratio of 9-(bis-methylsulfanyl-methylene)-2,7-dibromo-9H-fluorene and lithium tetrachlorocuprate is 25-50:1, stirring for 4-8 hours, adding sodium hydroxide solution, reacting for 10-20 minutes, collecting product by filtration, extracting filtrate with ethyl acetate, washing extract with sodium hydroxide solution, saturated sodium metabisulfite solution, and brine, drying over anhydrous sodium sulfate, removing excess organic solvent by distilling under reduced pressure, purifying by silica gel column chromatography using petroleum ether, and recrystallizing at -35 degrees C to -40 degrees C using 2-methylpentane. 9-(Bis-methylsulfanyl-methylene)-2,7-dibromo-9H-fluorene is obtained by adding potassium t-butoxide to dimethyl sulfoxide solution of 2,7-dibromo-9H-fluorene under anaerobic conditions such that the molar ratio of potassium t-butoxide and 2,7-dibromo-9H-fluorene is 2-2.4:1, mixing uniformly, adding carbon disulfide such that the molar ratio of carbon disulfide and 2,7-dibromo-9H-fluorene is 1-1.2:1, stirring of 10-20 minutes, adding methyl iodide such that molar ratio of methyl iodide and 2,7-dibromo-9H-fluorene is 1-1.2:1, reacting for 5-10 minutes, continuing reaction for 4-6 hours, pouring the reaction mixture into ice-water mixture for quenching, adding concentrated aqueous ammonia to remove unreacted methyl iodide, collecting precipitate by filtration, washing the precipitate, drying, and recrystallizing using a mixed solvent of ethyl acetate and tetrahydrofuran in a volume ratio of 2:1.    TECHNOLOGY FOCUS - POLYMERS - Preparation (claimed): Di(tetramethyl-dioxaborolanyl)alkylene-fluorene derivative of formula (II) and dibromo-dithieno-silole derivative of formula (III) are reflux-reacted in a molar ratio of 1:1 under anaerobic conditions in the presence of a solvent and a catalyst in alkaline environment for 2-72 hours, and the obtained product is separated and purified to obtain copolymer (I). Preferred Conditions: The molar ratio of catalyst and compound (II) is 0.005-0.05:1. The usage amount of alkali is 5-10 times the molar amount of compound (II). The separation and purification process involves extraction the reaction mixture with deionized water and organic solvent, collecting organic phase, removing organic phase by distilling under reduced pressure, precipitating using methanol, filtering the obtained solid, drying, dissolving the solid in organic solvent, removing catalyst by aluminum oxide column chromatography, and evaporating the solution to dryness.