One-pot Synthesis Of Conjugated Polymers And Polyisocyanide Diblock Copolymers And The Research Of Their Properties

In this paper, we designed and synthesized a variety of poly(phenylisocyanide) derivatives blocks, which were then introduced to the active chain ends of polythiophene and poly(phenyleneethynylene) derivatives respectively, afforded various novel "rod-rod" conjugated diblock copolymers. The stimuli-responsive, optical properties and self-assemblies of these polymers were then studied. Firstly, we synthesized a series of rigid diblock copolymers with tunable compositions and controlled molecular weights in one-pot using Ni(dppp)Cl2 as a single catalyst. These novel conjugated polymers were highly-soluble in water (higher than 10.0 g/L) and as a kind of stimulus responsive polymer material, they behave excellent multiple stimuli-responsive such as temperature, pH, and solvents. In addition, such block copolymers can be further utilized in living cell imaging. Secondly, we realized one-pot synthesis of hybrid block copolymers containing conjugated poly(phenyleneethylene) (PPE) and stereoregular poly(phenyl isocyanide) (PPI) using palladium(II) complex as a single catalyst. Although the two blocks were polymerized via distinct polymerization mechanism, the block copolymerization were revealed to proceed in a living/controlled chain-growth manner, afforded PPE-b-PPI block copolymers in high yields with controlled molecular weights, narrow molecular weight distributions, and tunable compositions. By AFM and SEM tests, we found that the thin film casted from the THF solution of PPE-b-PPI exhibited a well-defined helical nanofibrils morphology, while the thin film casted from toluene solution formed relatively larger nanofibrils. Meanwhile the amphiphilic PPE-b-PPI block copolymer self-assembled into well-defined spherical nanoparticles in the selective methanol solvent. Furthermore, we found that this polymerization method was applicable to a wide range of isocyanide monomers, thus a series of novel block copolymers were facilely prepared, including PPE-b-poly(1-isocyanohexadecane) (PPE-b-PIH) and PPE-b-poly(quinoxaline-2,3-diyl) (PPE-b-PQD) hybrid block copolymers, all possess remarkable photoluminescence properties.