The Study On Epoxy Adhesive Used In The Heat Exchanger

Adhesives used in heat exchangers require good heat resistance, excellent mechanical properties, for this problem, the paper developed a convenient construction, in line with the needs of the products of one-component epoxy adhesive. In this paper, epoxy resin as the main body, select several different fineness of dicyandiamide and its modifier (HT-18 curing agent, leaves curing agent, L curing agent) to study. Come through the curing temperature by differential scanning calorimetry (DSC), Curing trial in combination with curing reaction appropriate curing time. Detection through the shear, tensile, impact, bending, water resistance, high temperature testing, storage stability to find the best curing agent and its ratio. Through the performance of research, the choice of L-curing agent to meet the needs of the products, and coating on the impact of cross-section Carried out a study on analysis of surface topography by use of scanning electron microscopy (SEM), the toughening mechanism was discussed, and other performance-curing were also detected.In order to obtain a high peel strength, we must conducted toughening of epoxy resin modified. In this paper, the use of liquid acrylonitrile-butadiene rubber, Sunkist and EPG series of three one-component epoxy toughening agent for toughening modified. A test of modified epoxy resin adhesive's mechanical properties such as shear strength, peel strength, tensile strength by computer electronic universal testing machine, By contrast, in one-component epoxy adhesive to add a certain percentage of the EPG to get the best results.Best system through the experiment: epoxy resin 100g, L curing agent 12g, flexibilizer EPG30g, aluminum powder filler 20g, coupling agent KH-5503g. The system solidified under 193℃in 1 hour. Shear strength get 32.18MPa, peel strength get 2.67KN/m, the shear strength get 20.37MPa below 100℃, water absorption is 3.23 percent, and can stable storage at 0℃for 6 months. Fully meet the actual needs of applications (fast-curing, the shear strength of up to 25MPa, 100℃under the shear strength of up to 18MPa, peel strength up 2KN/m, water absorption below 5%, stable storage at 0℃for 6 months).