Аннотация:
Investigation revealed that alkyl chains in beta-position (fourth position of thiophene rings) lead to better pi-electron delocalisation due to enchanced planarity, because such position avoids rotational hinderance. Also, ramified alkyl side chains were found to be more appropriate for giving the compound better solubility. Additionally, change from linear alkyl chain to ethylhexyl branched solubilising side chain affected interaction between fullerene and polymer in bulk heterojunction devices. Synthesis of PPTDT2-CEHβ copolymer based on this chemical structure was performed and its physical and optoelectronical
properties were studied as well.