Synthesis Hyperbranched Polymer By A Controlled One-step Process And The Research Of Carboxyl-funtionalized Hyperbranched Polyester As Tougher For Epoxy Resin

This article provides a controlled one-step process for preparing a hyperbranched polymer with benzenyl unit. The controlled one-step process is to add core monomers and drop monomers into the reaction system. Polymerization of monomer benzyl choride/benzyl bromide have been carried out under condition using ferric chloride anhydnous/aluminum chloride anhydnous catalyst with benzene/benzene derivate used as core monomer and carbon-disulfide as solvent. The molecular weight distribution of resulting hyperbranched polymer is very narrow and the molecular weight can be adjusted. This reaction system is investigated in different condition such as comparing novel synthesis method with old synthesis method, monomer, core monomer, catalytic agent and dropping speed of monomer. The conclusion collectively indicate the following:(1) Comparing novel synthesis method with old synthesis method, the molecular weight distributions of resulting hyperbranched polymer which are different. The result of novel synthesis method is narrower than those two. And the molecular weight can be controlled easier by the controlled one-step process.(2) Adding higher reaction activity core monomer and core monomer which have more B group into the reaction system, the molecular weight distributions of resulting hyperbranched polymer which are prepared by these three methods are not different widely. But the molecular weights are different widely. The reason of this phenomenon is that more active core monomers are effected on steric hindrance and the core monomers which have more B group are effected on reaction activity.(3) The molecular weight of product can be better controlled by the controlled one-step process when monomers have higher reaction activity.(4) Two conclusion can be gotten when catalytic agent content is changed. First, the molecular weight distributions of product has the minimum at one range when catalytic agent content is decreased. No product can be got when catalytic agentcontent is decreased to one value. Second, the molecular weights of product are stable when catalytic agent content is decreased.(5) No regular pattern is not gained in the research of dropping speed. The reason is that the reaction control is effected by the accumulation of the less monomer activity in the reaction system.These experiment results show that the controlled one-step process can get the product that has narrower molecular weight distribution and the molecular weight can be better controlled. Therefore, the controlled one-step process is one of ideal processes to preparing hyperbranched polymer.The carboxyl-funtionalized hyperbranched polyester as tougher for epoxy resin is also studied in this paper. The glass transition temperature of the thermoset decrease with the increased of the content of the hyperbranched polyester content is and there is peak disintegrate in the spectra. The phenomena are the same when the adding hyperbranched polyester which ending-group is hydroxy and ester group. But phase separation is not observed by scanning electron microscope(SEM). The thermomechanical properties and morphyology of blends of the carboxyl funtionalized hyperbranched polyester and epoxy resin is not decisive. To determine whether the carboxyl-funtionalized hyperbranched polyester is tougher for epoxy resin, compact tension experiment is needed.