Synthesis, Characterizations And Self-assembly Of Hyperbranched Polyimide Based On Sydnone Click Chemistry

Since hyperbranched polymers (HBPs) have been prepared successfully, they were popular used in the field of functional membrane materials, materials for drug delivery, nano materials, due to the excellent performance, novel structure as well as simple synthesis method, attracting many research people’s attention. Recently, HBPs have been focusing on seeking more convenient green approaches, improving the degree of branching (DB), preparing well-defined structure, thereby sloving problems such as low DB, wide molecular weight distribution,easy to gel and promoting the industrial production. What’s more, with the emergence is of self-assemble of hyperbranched polymer, severe challenges have been faced. It is urge to develop more amphiphilic block copolymers based on hyperbranched polymer, studying self-assemble behavior.Above all, we studied our research by hinging around two new hot spots. The thesis comprises two primary parts of research contents. The first part including Chapter 2 and 3, describes the synthesis and characterization of A(A’)+B3 type of HBPI and AB(B’) type of HBPI. The second part is the 4th Chapter, mainly set out the synthesis and self-assemble of amphiphilic hyperbranched multiarm copolyimides.In Chapter 2, we prepared an A(A’) monomer containing sydnone and two B3 monomers with maleimide. Based on dual cycloaddition of sydnone and maleimide, a series of HBPI with high DB, moderate molecular weight, narrow molecular weight by one-pot method have been synthesized. Then we investigated the effect of reaction time, monomer molar ratio, solid content and other factors, besides the solubility and thermodynatic properties.In Chapter 3, we first prepared a new type of AB(B’) monomer containing sydnone and maleimide, then synthesized HBPI with moderate molecular weight, narrow molecular weight and 100% DB, on the basis of dual cycloaddition of sydnone and maleimide. What’s more, we prepared a model compound, monitoring the process of reaction.Then we discussed the reaction mechasium from the point of view of reaction dynamics, then studied solubility and thermodynatic properties.In Chapter 4, we synthesized a series of amphiphilic hyperbranched multiarm copolyimides through click chemistry by using the core-first strategy. Study on self-assemble behavior and morphologies was carried out by controlling the water content, the polymer concentration, the arm number of hydrophilic, the volume of hydrophilic, characterized by DLS, TEM.