The ability to control supramolecular assemblies of π-conjugated polymers (CPs) in thin films is essential for the development of organic optoelectronic devices because collective functions and properties of the CPs strongly depend on the interpolymer overlap of the molecular orbitals (i.e., π–π stacking) [1]. On one hand, arranging π–π stacking facilitates interwire charge carrier transport, whereas, on the other hand,1 preventing π–π stacking leads to unique photophysical and mechanical properties [2].
In this presentation, we have revealed an unexplored potential of the CTP method in terms of steric hindrance, along with a demonstration of chain-growth polymerization of isolated CPs. The synthesized CPs has a fenced and well-developed conjugated backbone with a narrow polydispersity, and therefore, can be regarded as a new type of isolated CP [1,2]. Furthermore, on the basis of this finding, we have synthesized all-polythiophene diblock copolymer, in which one block is naked and the other is fenced. The naked P3HT block self-assembles through π–π stacking, thereby inducing microphase separation. As a consequence, we have succeeded, for the first time, in creating a microphase separation comprising an ensemble of stacked and isolated polythiophenes. We believe that such a sophisticated control over π–π staking in a polymeric thin film will extend the use of these materials into various unprecedented applications owing to the synergy of the contrasting properties of the two blocks [3].
References (1) Sirringhaus, H.; Brown, P. J.; Friend, R. H.; Nielsen, M. M.; Bechgard, K.; Langeveld-Voss, B. M. W.; Spiering, A. J. H.; Janssen, R. A. J.; Meijer, E. W.; Herwig, P.; de Leeuw, D. M. Nature 1999, 401, 685. (2) Pan, C.; Sugiyasu, K.; Wakayama, Y.; Sato, A.; Takeuchi, M. Angew. Chem. Int. Ed. 2013, 52, 10775. (3) Pan, C.; Sugiyasu, K.; Aimi, J.; Sato, A.; Takeuchi, M. Angew. Chem. Int. Ed. 2014, 53, 8870.