| Epoxy resin adhesive are widely used for its excellent performance such as low shrinkage, dimensional stability, excellent electrical properties, resistance to chemical media, good bonding ability to a variety of material, etc. But there are also some disadvantages of low adhesive strength, brittleness, heat resistance. This thesis focuses on two-component adhesives which the mixture of common bisphenol A epoxy resin and phenolic epoxy resin was to be the component A. Adhesives cured on the conditions of room/medium temperature with the amine curing system. Using nano/micron reinforced materials with different morphology to modified epoxy resin adhesive, which are nano-SiO2 (zero-dimensional), potassium titanate whiskers (one-dimensional) and nano-organic montmorillonite (two-dimensional). Disused the best adhesive curing process conditions, and studied the effect to adhesive properties, viscosity and thermal properties by three kinds of reinforced materials. In addition, the percolation theory model of three reinforced materials toughened on epoxy resin is preliminarily explored.The results show that:The effect of reinforced materials modified epoxy adhesive is remarkable. The optimum conditions for adhesive is as follows:15wt% diluent content, DDM+593 as curing agent,80℃/4 hours curing. The bond strength of steel pickling treatment after sanding is significantly higher than untreated surface. And the heat-resistant of adhesive is also improved when reinforced materials added. The application of adhesives is unrelated to the type and the amount of reinforced materials. But related to the temperature of sizing, as the environmental temperature of sizing increased, the application shorted. When the addition of 2wt% can lower the viscosity, and show some of the thixotropic property. Reinforced materials can greatly improve the steel-steel shear strength and impact strength of adhesive. SEM pictures of impact fracture showed that the three kinds of reinforced materials have different mechanisms on toughening of adhesive. Nano-SiO2 is mainly by causing crazes and microcracks in the resin matrix to absorb some part of impact energy to toughening. When adding PTW, the crack deflection, whisker pull-out and whisker debonding phenomenons emerged, so the toughening mechanisms is passivating crack tip and preventing crack propagation. And cured resin content with OMMT formed a number of different levels of fracture surfaces when shocked, so the stress can be dispersion and then toughed the adhesive.The paper established a model of percolation theory according to the impact properties of three kinds of reinforced materials modified epoxy resin. The calculations proved that the toughening behavior all of three reinforced materials are in line with percolation theory. It suggesting that three kinds of reinforced materials in the adhesive play a role of crosslinks, then formed the enhanced areas in adjacent to the polymer matrix. So these areas interconnected and impenetrated then form an infinite percolation cluster, ultimately achieved the effect of toughening polymer. Epoxy adhesive modified with reinforced materials have excellent comprehensive properties, the technics is simple and low cost. So the method which reinforced materials modified epoxy adhesive has a positive promotion and application value in the field of structural adhesives.
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