Study On Epoxy Resin Structural Adhesive Modified By Nanophase Materials

Civil engineering come into a boom time along with the rapid development of social economy, but it is imminence that the old building need reinforcement and repariement because aging, sudden damage or modern rebuilding, when buildings are increasing. As a new building material for reinforcement and strengthening, the supply and application of epoxy resin structural adhesive are more and more, but standard structural adhesive itself has the disadvantages such as worse working performance, low bond strength, brittleness,low elastic ratio. So it is necessary to modify the structural adhesive.Epoxy resin structural adhesive was modified by nanosize SiO₂ , nanosize CaCO3 and Organic-Montmorillonite in the paper,respectively. Effect law of different materials on the properties of structural adhesive were studied and the modifying mechanism was discussed by microcosmic testing method.Results showed that,when nanosize SiO₂ dispersed in the epoxy base ,effect of nanosize SiO₂ on working performance was changed obviously, on bond strength, impact strength and heat distortion property were good. When nanosize CaCO3 dispersed in the epoxy base,effect of nanosize CaCO3 on working performance was good, on bond strength,impact strength and heat distortion property were very good. Combination of nanosize SiO₂ and nanosize CaCO3 were able to engender combination effect,the working performance and bond strength were increased evidence. It was benefited that the cost of structural adhesive was descended by nanosize CaCO3 replaced some nanosize SiO₂,too. Organic-Montmorillonite and epoxy resin were intercalated and compounded by curing at 80℃.The mechanical properties were improved obviously, steel-steel shear strength and impact strength were most advanced thereinto. SEM results showed that, microcrack induction ability of these materials was markness.In a word,the working performance,bond strength, elastic ratio,brittleness of structural adhesive modified by proper materials were improved,satisfied engineering requirement. Its modifying technology was simple and convenience,has very high active extending sense and application value in structural adhesive modifying field.