Tetraphenylethene-Functionalized Conjugated Helical Poly(phenyl isocyanide) with Tunable Light Emission, Assembly Morphology, and Specific Applications

Aggregation-induced emission (ALE) active tetraphenylethene (TPE) functionalized phenyl isocyanide (PI) derivatives, such as TPE pendent PI monomers (TPE-NC) and TPE-based Pd(II) catalysts (TPE-Cat. a and TPE-Cat. b) were synthesized. The corresponding linear (poly(TPE-NC)) and four-armed (TPE-[poly(TPE-NC)(m)](4)) conjugated polymers were subsequently prepared through the living polymerization of TPE-NC with TPE-Cat. a or TPE-Cat. b in THF, respectively. All of them have good solubility in common organic solvents, such as THF and CHCl3, and exhibited tunable ATE property, which can be facilely tuned through the variations on the concentration and the molecular weights (MWs) of the polymers. They also showed excellent thermal stability with a 5% of their weight loss as high as 380-405 degrees C and significant mass loss in the range of 350-650 degrees C. Stable helical assemblies could be formed by poly(TPE-NC). at high concentration conditions. However, four-armed TPE-[poly(TPE-NC)(m)](4) could self-assemble into an apparent bumpy caterpillar like assembly, which was very different from the ordinary ones. Moreover, these conjugated polymers could be employed to generate a vapochromism phenomenon and act as good dispersants for carbon agglomerates in poor solvents. It is expected that this work can enrich the family of luminescent materials based on the helical poly(phenyl isocyanide) main chains and guide the future design of optical materials with attractive structures and special purposes, such as heat-resistant materials, security materials, and dispersed materials.