Organic Solvent Free Synthesis and Processing of Semiconducting Polymers for Field Effect Transistors in Waterborne Dispersions

Conjugated semiconducting polymers are key active materials for printable electronics, sensors and biosensors, organic photovoltaics, organic light emitting devices, and more. The research in the field developed very efficient materials and sound structure property relationships, thus making a case for a transition from laboratory to industrial environment. At this critical juncture, sustainability, and ease of scaling up are at least as important as performances, to the point that efficient materials on a lab scale could become unpractical for the industry. The development of more efficient synthetic protocols and the complete removal of all organic solvents from both the synthesis and the processing of semiconducting polymers can help tremendously to improve sustainability and reduce costs. It is shown that the use of an aqueous dispersion of the food grade surfactant lecithin as the medium, enables the synthesis and processing of the representative semiconducting alternating copolymer poly (9,9-dioctylfluorene-alt-bithiophene) (PF8T2) in high yield and high quality and with transistor performances comparable with those obtained with reference materials synthetized and processed from volatile organic solvents.