Processing of Conjugated Ladder Polymers

The fused-ring backbone constitution of conjugated ladder polymers (cLPs) imparts them with intriguing and favorable chemical, optical, and electronic properties. However, in the context of processing them into desired forms such as fibers, films, or membranes, significant challenges are imposed by the high melting points and poor solubility. To address this challenge, various processing strategies have been developed, which offer promise for practical applications. This chapter summarizes reported methods and examples on this topic, which can be categorized into (i) direct solution-processing methods and (ii) in situ reaction methods after processing a precursor. For solution-processing methods, the desired solubility or solution dispersibility of cLPs can be achieved by using acidic solvents, covalent attachment of solubilizing groups, construction of nonplanar backbones, or processing solution-dispersed nanoparticles. For in situ reaction approaches, a number of highly efficient solid-state reactions have been employed and investigated.