Facile strategies to improve the economy of polymer synthesis and self-assembly

Abstract

Preparation of polymers and their self-assembled nanostructures with high controllability, efficiency, and economy is central basis for the development of polymeric nanomaterials. To address this issue, following four chapters described facile strategies for the synthesis and self-assembly of polymers with economic consideration. Chapter 2 described the concept of step-economic in situ nanoparticlization of conjugated polymers (INCP) with addressing the effect of core forming block. Poly(para-phenylene) was used as first block, and highly insoluble polythiophene or poly(3-methylthiophene) was used as second block to induce in situ self-assembly. We found that solubility and packing mode of second block were important factors to determine nanostructures. Chapter 3 described step-economic in situ nanoparticlization of conjugated polymers with addressing the effect of shell forming block. Poly(3-alkylthiophene) was used as first block, and highly insoluble polythiophene was used as second block to induce in situ self-assembly. It was found that hydrodynamic volume of first block and well-defined polymer structure were important factors to modulate the shape of nanostructures. Chapter 4 presented the price-economic synthesis of the conjugated polymers using recyclable Pd-Fe3O4 heterodimer nanocrystal. AB-alternating copolymers were synthesized by Suzuki-Miyaura polycondensation with Pd-Fe3O4 nancrystals. Significantly, Pd-Fe3O4 bimetallic nanocrystals were easily recovered by magnet and recyclable with minimal Pd leaching. Chapter 5 reported the atom and step-economic synthesis of poly(N-sulfonylamidine)s using Cu-catalyzed multicomponent polymerization. Optimization of polymerization condition enabled the synthesis of poly(N-sulfonylamidine) with high molecular weight and yield. Furthermore, this polymerization expanded to the library synthesis of poly(N-sulfonylamidine). This research is significant because this polymerization overcome previous limitations such as low molecular weight, defect in polymer structure, and narrow substrate scope. In summary, this thesis described economic synthesis of polymers and self-assembled nanostructures via INCP, heterogeneous catalysis, and multi-component polymerization. We believe that these strategies will expand their scope and suggest a new platform for the preparation of useful nanomaterials.