Upscaling and optimisation of the reaction conditions for direct arylation polymerisation

To realise the fabrication of larger organic solar cells, we have upscaled polymer donors and polymer acceptors as well as a small molecule non-fullerene acceptor. The traditional polymerisation method used to synthesis high molecular weight conjugated polymers is transition-metal-catalyzed cross-couplings, especially Stille coupling that requires the use of toxic organotin compounds. To synthesis polymers in a more environmentally friendly way, we have explored the reaction conditions for direct arylation polymerisation, avoiding the use of organotin compounds. In addition, the optimised condition of the direct arylation method offered high yields and high molecular weights. Our results demonstrate a green way of upscaling the synthesis of conjugated polymers.