초록 |
Molecular weight of conjugated polymer is a critical factor that determines material properties and device performances. To avoid batch-to-batch variations of molecular weight in conventional batch reactor, we developed a flow synthesis system that can perform step-growth Stille polycondensation in a reproducible manner. By utilizing nitrogen gas as a carrier, our flow system provides uniform and precisely controlled reaction conditions without a common head and tail diffusion problem in other flow systems. We conducted Stille polycondensations to synthesize various donor (D)-acceptor (A) type conjugated polymers and monitored the polymerization process over the residence time. As an example, a representative conjugated polymer PTB7 was synthesize with a high average molecular weight (Mn) of 34.2 kDa and Đ of 1.93 in only 3 min with high reproducibility (3.1 % errors for Mn between runs). |