ScholarWorks@성균관대학교

초록

The synthesis of n-type semiconductors traditionally relies on the environmentally harmful Stille organotin polymerization. Here, we report the optimized direct arylation polymerization (DARP) of an electron-transporting polymer, poly[2,7-bis(2-decyltetradecyl)-4-methyl-9-(2 '-methyl-[5,5 '-bithiazol]-2-yl)benzo[lmn]-[3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone], P(NDI2DT-Tz2). A series of PNDITZ-Mn polymers with molecular masses (M n) from 6.5 to 32.9 kg mol-1 was synthesized and investigated for charge transport and thermoelectric properties. Optimized DARP conditions yielded PNDITZ-19 K (M n/D = 18.8 kg mol-1/2.8), comparable to Zn-PNDITZ prepared via the anionic zinc protocol (16.4 kg mol-1/2.39). Thermal, UV/vis, and VT-NMR analyses confirmed that PNDITZ-19 K displays photophysical properties and structural integrity indistinguishable from those of Zn-PNDITZ. Charge transport and thermoelectric measurements gave sigma approximate to 2 & times; 10-2 S cm-1 and a power factor near 1 mu W m-1 K-2. GIWAXS analysis revealed that polymer crystallinity correlates directly with M n/D, with PNDITZ-19 K showing the best performance across the series and approaching that of Zn-derived materials. Notably, DARP-synthesized P(NDI2DT-Tz2) achieved a 15-fold reduction in the E-factor (7.23 vs 108.65), highlighting its much lower environmental footprint. These results establish DARP as a sustainable and efficient method for producing high-quality n-type semiconducting polymers.

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