Synthesis Of Topological Polymers Through The Combination Of ATRP And CuAAC Catalyzed By Fe（O）/CuBr₂ In One-Pot

Recently, topological polymers such as star polymers and cyclic polymers have attracted increasing attention because of their special unique properties, such as clear structure, low viscosity and versatility compared with that of linear polymers with similar chemical compositions and molecular weights. In addition, using topological polymers as functional materials have received considerable attention because of a wide range of potential applications in biomedical medicine, nanotechnology and material modification due to their special properties.However, the topological polymers are very difficult to be fabricated attributed to their complicated structures, multistep reaction and poor controllability. Therefore, it will be great advantageous to find a simple and efficient synthetic method for topological polymersIn this paper, by investigating catalytic capability of the catalyst for one-pot reaction we discover that one-pot reaction is successfully employed to design linear and star polymers by combination ATRP and copper(I)-catalyzed azide-alkyne cycloaddition(CuAAC) reaction catalyzed by Fe(0)/CuBr2. Moreover, we exploite the feasibility of one-pot reaction to prepare cyclic brush- like polymers by combination ATRP and CuAAC step-growth polymerization catalyzed by Fe(0)/C uBr2. Following research work has been done in this paper:(1) To screen Fe(0)/C uBr2 as catalysts to catalyze the ATRP and CuAAC reaction in one-pot, we investigate catalytic performance of the different catalyst. Then, two different initiators(linear and star) are used to trigger the model reaction catalyzed by Fe(0)/C uBr2, and the polymerization kinetics are investigated.The results indicate that polymerization behaviors possess the characteristics of ??living??/controlled radical polymerization. Furthermore, the FT-IR, NMR, MALDI-TOF MS data confirm that the rate of click reaction are much faster than the polymerization rate in one-pot. All the results demonstrate that Fe(0)/C uBr2 catalyze one-pot technique could prepare well-controlled linear and star polymers with narrow molecular weight distribution.(2) A novel trifunctional initiator containing one alkyne group, one azide group and one bromo group has been designed. Then, one-pot technique via a combination ATRP and CuAAC step-growth polymerization is employed to produce the well-controlled cyclic brush-like polymers catalyzed by Fe(0)/C uBr2 and initiated by the trifunctional initiator. Our works provide a new idea for the preparation of the cyclic brush-like topological polymers.