Synthesis, structure and function of π-stacked polymers

Macromolecular conformation often has a significant effect on the properties of polymeric materials, and hence, conformational control in synthesizing a polymer is an important goal in polymer science. As a new conformational motif of vinyl polymers having side-chain pi-electronic groups, we have introduced a 'pi-stacked structure' in which side-chain chromophores are regularly stacked on top of each other and main-chain C-C bonds have a nearly all-trans, zigzag conformation. pi-Stacked polymers can be prepared by vinyl polymerization of dibenzofulvene (DBF) and its derivatives. On the basis of the controlled structure, poly(DBF) and its derivatives exhibit unique photophysical and electronic properties as vinyl polymers. In addition, introduction of chirality to pi-stacked polymers was also achieved. In this review, the synthesis of poly(DBF) and its derivatives and their structural analyses and properties are described. Polymer Journal (2010) 42, 103-123; doi:10.1038/pj.2009.332