Synthesis And Characterization Of Hyperbranched Polymers By Applying A Superelectrophilic Reaction

Highly branched polymers are emerging a new type of molecular functional materials nearly two ecades, because of its novel structure and unique performance, making it one of the hot polymer researches in the field. Dendrimers and hyperbranched polymers are two different approaches. Dendrimers are monodisperse, globular, perfectly branched and the terminal groups are located on the surface of the molecule. The production of dendrimers, however, requires multistep syntheses making it a costly and time-consuming process. Hyperbranched polymers, in contrast, are easily prepared from monomers of ABx-type in a straightforward one-step synthsis. Hyperbrached polymers, like dendrimers, a number of fuctional groups, low viscosity, a high segment density. Therefore, they provide a less expensive alternative to dendrimers for various applications, such as the production of blended components, photosensitive materials, nonlinear optics, drug delivery, and use as catalysts.In this dissertation, we used a new convenient "A2+B3" approach by superelectrophilic reaction to synthetise hyperbranched polymers. Firstly, we used acenaphthene as raw material to synthetise a series of A2monomers like5-bromoacenaphthene,5-nitroace-naphthene,5-metroxyacenaphthene and5-aminoacenaphthene. And we used phenyl ether and benzene tricarbonyl tricholoride to synthetise B3molecular (1,3,5-tri-(4-phenoxybenzoyl)-benzene), that has three functional groups.Then, we discussed the different reaction time, reaction temperature and different substituents on the impact of polymers, we obtained after24h reaction and prolong the reaction time did not affect the polymer molecular weight large, the higher the temperature, polymer molecular weight reduction, substitution for the power base polymer molecular weight decreased as the electron withdrawing substituent, the molecular weight increases. Our obtained optimum temperature of the reaction conditions is25℃, time24h, in superacid condition, as well as methanesulfonic, we used A2monomers and B3molecular to synthetise hyperbranched polymers by superelectrophilic reaction to avoid the gel formation phenomenon. Last, the resulting polymer was characterized by NMR spectroscopy and gel permeation chromatography (GPC). We used acenaphthoquinone and replace acenaphthoquinone A2monomers were replaced by isatin, increased reactivity, it makes the strength of acid catalyst can be greatly reduced, can be replaced with a methyl sulfonate trifluoromethyl sulfonic acid, reduced the response costs, and increase the safety factor of the reaction, which is the main innovation of this experiment one.In addition, we studied the effect which different experimental conditions and the A2monomer on the polymer structure and properties.