TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I) comprises adding 2,5-divinyl-benzene compound of fomula (A) and 4,7-bis(5-bromo-2-thienyl)-5,6-difluoro-benzotriazole compound of formula (B) to an organic solvent containing a catalyst present in a molar ratio of 1:1 in an oxygen-free environment, performing a Heck coupling reaction for 24-96 hours at 70-130 degrees C, and obtaining (I). Preferred Method: The method further comprises purifying the difluoro-benzotriazolyl organic semiconductor material. Preferred Components: The catalyst is organic palladium or a mixture of organic palladium and organic phosphorus ligand. The organic palladium is at least one of bis(triphenylphosphine)palladium(II) dichloride, tetrakis(triphenylphosphine)platinum and palladium acetate. The organic phosphorus ligand is tri-o-tolyl phosphine. The organic palladium and 1,4-dimethoxy-2,5-divinyl-benzene is present in a molar ratio of 1:20-1:100. The organic solvent comprises toluene, N,N-dimethylformamide or tetrahydrofuran. The reaction temperature of the Heck coupling reaction is 90-120 degrees C, and the reaction time of the Heck coupling reaction is 48-72 hours. EXAMPLE - 116 mg of 2,5-Di-n-octyloxy-1,4-divinylbenzene, 176.8 mg of 2-n-octyl-47-bis(5-bromo-thienyl)-5,6-difluoro-1,2,3-benzotriazole, 10.1 mg of palladium acetate, and 3 mg of tri-o-methoxy phosphorus were dissolved in a flask containing 12 ml of N,N-dimethylformamide to form a solution. The nitrogen was sufficiently introduced to the flask to exhaust the air for 30 minutes, a Heck coupling reaction was performed for 48 hours at 120 degrees C. The polymerization reaction was stopped after cooling, and a reaction solution was obtained. Then 40 ml of methanol was added to the flask, the reaction solution was precipitated, filtrated, then was extracted and precipitated with methanol and hexane for 24 hours. The reaction solution was then extracted and precipitated using chloroform as a solvent until the reaction solution turned colorless. The chloroform solution was collected and evaporated to obtain a red powder, which was then dried under vacuum at 50 degrees C for 24 hours to obtain 57% of poly(2,5-di-n-octyloxy-1,4-divinyl benzene-co-2-n-octyl-4,7-dithienyl-5,6-difluorophenyl-benzotriazole).