Studies On Toughening Of Epoxy Resin By Useing A Polymer With Active Epoxy Groups

A new kind of copolymer named PBG was synthesized through copolymerization of butyl methacrylate (nBA) and glycidyl methacrylate (GMA). The copolymerization rate of the two monomers had been studied firstly. And then, a series of copolymers PBG1, PBG2 and PBG3 were obtained by adding different monomer ratio based on the above results. Delivery ratio of monomer nBA/GMA were 10/1, 9/1 and 8/2. The structures and properties of the polymers were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance (NMR), and gel-permeation chromatography (GPC).The copolymers were used for modifying properties of epoxy resin E-44. The effcts on properties of epoxy resin caused by different polymers and different content of polymers in epoxy resin were studied. The curing kinetics equation was obtained through the curing kinetics study. The mechanical and thermal properties test results showed that the PBG had a satisfactory toughening effect on the E-44 in many aspects. The best modification effect could be obtained when the polymer were selected PBG2, and the content was 5/100-10/100. The thermal properties such as glass transition temperature and Vicat softening temperature were improved, decomposition temperature had no change. Scanning electron microscope photographs explain the mechanism of toughening.At the same time, the solid epoxy resin E-663 was modified by PBG using the same method. The test results of mechanical and thermal properties also showed that a better toughening effect could be get when the adding amount 5/100-10/100. Similarly, the polymer PBG toughening solid epoxy resin was studied through SEM, XRD and so on.