Influence of chemical modifications on intermolecular ordering and orientation in semiconducting polymers

Abstract

In this thesis three different series of semiconducting polymers were investigated. Their phase behavior in bulk was studied using DSC and WAXS, while their ordering, preferred crystal orientation and surface morphology in thin films was investigated using GIWAXS and AFM. In the first investigated series it was found that adding polar end groups to the side chains of polythiophenes results in a complete face-on orientation of crystals in thin films. In the second series of polythiophenes with ethylene glycol side chains it was found that the linkage (alkyl spacers of different length) of the side chain to the backbone significantly influences the crystallinity and the performance in OFET and OECT devices. In the third series of PDPPs with different chemical modifications it was found that the intermolecular ordering is significantly affected by the introduced chemical modifications and that the ordering can be well described with sanidic liquid crystalline mesophases.