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Heat exchangers used in adhesives require heat resistance, excellent mechanical properties , for this problem , we developed a convenient construction , in line with the one-component epoxy adhesive product needs . In this paper , an epoxy resin as the main study choose between several different fineness of dicyandiamide and its modified product curing agent ( HT - 18 curing agent for the leafy curing agent , L curing agent ) . The curing temperature is obtained by differential scanning calorimetry (DSC) , combined with the curing experiment showed that the curing reaction of suitable curing time . Detected through shear , tensile , impact , bending, to find the best water resistance, high-temperature test , the storage stability of the curing agent and proportioning . Through the study of the performance , select L curing agent is able to meet the demand for products . In order to obtain the high peel strength , epoxy toughening modification . This article uses liquid nitrile rubber, Sunkist Series and EPG The three tougheners component epoxy toughening modification . The microcomputer electronic universal testing machine tensile test was conducted to test the modified epoxy resin adhesive shear strength, peel strength , the main body tensile strength and other mechanical properties , and using a scanning electron microscope (SEM) of the coating film impact fracture the surface morphology analysis, the toughening mechanism , have also been detected on other properties of the cured . Through comparative analysis , adding a certain percentage of one-component epoxy adhesive EPG can get the best results. Obtained through experiments the best system : epoxy resin 100g , L curing agent 12g toughening agent EPG30g , 20 g of aluminum powder filler , coupling agent KH - 5503g . This system is cured in a 193 ° C under 1 hour. Shear strength of 32.18MPa, the peel strength of 2.67KN / m , 100 ° C under a shear strength of 20.37MPa , water absorption was 3.23 % , but also storage stable for 6 months at 0 ° C under . Fully meet the needs of practical application of the product ( fast curing , the shear strength of 25 MPa , 100 ° C under a shear strength of 18MPa , the peeling strength of up to 2KN / m , the water absorption of less than 5% , can be storage stable at 0 ° C under 6 months or more ) .
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