1：Experimental Design and Method Selection:

The study involved synthesizing a modified polymer P1 through a series of chemical reactions including dimerization, cyclization, tosylation, N-alkylation, bromination, Stille's and Suzuki's coupling reactions. Various analytical techniques were used to characterize the properties of P

2：Sample Selection and Data Sources:

The polymer P1 was synthesized and compared with the previously reported PCDTBT. Samples were prepared in solution and solid states for analysis.

3：List of Experimental Equipment and Materials:

Instruments included JOEL ECA 600 NMR, Perkin-Elmer FTIR-ATR, GPC system with Waters 1515 HPLC and Waters 2414 RI detector, JEOL JSM-5610LV SEM, Metrohm Autolab PGSTAT204 potentiostat/galvanostat, Agilent Technologies Cary 60 UV-Vis spectrometer, and TGA. Materials involved chemicals for synthesis and solvents like toluene and chloroform.

4：Experimental Procedures and Operational Workflow:

Synthesis was carried out as per Scheme

5：For characterization, NMR and FTIR were used for structural confirmation, GPC for molecular mass, SEM for morphology, cyclic voltammetry for electrochemical properties, UV-Vis for optical properties, and TGA for thermal stability. Data Analysis Methods:

Data were analyzed using standard equations for energy levels and band gaps, with comparisons made to literature values for PCDTBT.