Synthesis and Property Study of Multilayer 3D Conjugated Polymers via Suzuki Miyaura and Sonogashira Coupling

Polymers are a central class of materials that play an important role in both daily life and advanced technologies. Among them, conjugated polymers have been widely studied because of their unique optical and electronic properties, combined with light weight and ease of processing. Their performance is not only determined by the repeating chemical units but also by the overall three-dimensional arrangement of the chains. In particular, π-stacked and multilayered polymer frameworks provide an effective way to improve conductivity, charge mobility, and luminescence by enabling through-space interactions between aromatic units. Despite their promise, such systems remain relatively underexplored. Recent progress in palladium-catalyzed cross-coupling reactions has opened reliable pathways for the synthesis of multilayer three-dimensional polymers. Strategies based on Suzuki–Miyaura and Sonogashira couplings have been especially valuable, allowing the construction of well-defined frameworks with controlled structures. These methods have further enabled the design of polymers exhibiting aggregation-induced emission (AIE), a phenomenon where emission is enhanced in the solid or aggregated state. This property is particularly important because it contrasts with the emission quenching seen in traditional fluorophores and provides opportunities for stable fluorescence in practical settings. In this thesis, two sets of multilayer polymers were synthesized using palladium-catalyzed approaches. The Suzuki–Miyaura strategy yielded a class of four polymers, while the Sonogashira method was applied to obtain five related polymers. Their structural and functional features were examined through Fourier-transform infrared spectroscopy (FT-IR), optical absorption studies, luminescence measurements, and thermal analysis techniques including thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). These investigations highlight how controlled molecular design influences stability, photophysical behavior, and structure–property relationships in multilayer three-dimensional polymers. Overall, the results contribute to a clearer understanding of conjugated polymer architectures and provide useful insights for the continued development of advanced organic materials.