The Research On Aging Resistance Of Epoxy Adhesives In Comprehensive Environmental

In this paper,the 1670 T and 1670 B epoxy curing agents were choosen to cure the epoxy resin E-51 respectively at room temperature,and 2wt % of nano SiO₂ modified the epoxy adhesive.The sheet and dumbbell-like mechanical tensile samples of epoxy adhesive were prepared by self-designed mould with self-groped method.The samples were ET?E-51 cured by 1670T?,EB?E-51 cured by 1670B?,ETS?E-51 cured by 1670 T,modified by 2wt % of nano SiO₂?and EBS?E-51 cured by 1670 B,modified by 2wt % of nano Si O₂?.The UV/T/P and T/P comprehensive environmental aging test of epoxy adhesives were performed by using self-designing aging equipment.These samples were evaluated by color difference,yellowness index,weight,attenuated total relectance-Fourier transform infrared spectrum,micro morphology and tensile strength.The modification effect of epoxy resin adhesive and comprehensive environmental aging resistance were researched through these test methods.In the alternating temperature / low air pressure aging environment,with the increase of aging time,the color and the yellowness index of the samples increased;all the ether bond peaks increased first and decreased then,and the infrared absorption peak of carbonyl group increased;the sample weight was reduced in different degree;the surface morphology of the samples changed;the tensile strength increased first and decreased then.The relative variation of the nano SiO₂ epoxy resin adhesive was more obvious than that of the pure epoxy resin adhesive.Nano SiO₂ epoxy resin adhesive significantly improved the aging resistance of E-51 epoxy resin adhesive.In the UV / temperature / low pressure alternating comprehensive aging environment,with the increase of aging time,the color and the yellowness index of the samples increased;the ether bond IR absorption peaks increased first and decreased then,the carbonyl characteristic IR absorption peaks increased;the weight of sample reduced;the surface morphology of the nano SiO₂ epoxy resin adhesive samples changed more largely than pure epoxy resin adhesive samples;the tensile strength of the samples increased firstand decreased then.The improvement of aging resistance of E-51 epoxy resin adhesive by nano SiO₂ was obvious.Under the same aging environment,the resistance to aging degree was similar comparing the two epoxy resin cured by different cure agents,but the epoxy resin cured by 1670 B was a little yellow.Moreover,compared to the same sample in two kinds of characterization results in two kinds of aging environment,under the UV/T/P comprehensive aging environment,the samples aged more seriously,and the modification effect of nano SiO₂ to the aging resistance performance was more significant.