The Research On Comprehensive Environmental Effect Of Modified Epoxy Adhesives

The antioxidant-1010 and composite additives contains antioxidant-1010 and silicon dioxide nanometer were choosed as modifying agent to modify epoxy adhesive E-51 in this paper. A pure E-51, antioxidant modified E-51 and composite additive modified E-51 epoxy adhesives thin films were prepared by spin-coating. The Single lap shear specimens of the epoxy adhesives were prepared by a self-designed mould. The UV/O₃/T/P and O₃/T/P comprehensive environmental aging test of epoxy resin adhesives were performed by using self-designed aging equipment. The aging behaviors of the samples were evaluated by color difference,yellowness index,Fourier transform infrared spectra, micro morphology and tensile shear strength. The comprehensive environmental effect of epoxy resin adhesives and the affection of addition agent on comprehensive environmental effect of epoxy resin adhesives were researched, and the UV radiation effect was analysied.Under UV/O₃/T/P comprehensive environmental exposure, the color difference and yellowness index increased gradually as aging time increases. The area of methyl/methylene and ether linkage decreased gradually as aging time increases, while the area of carbonyl increased gradually. The chromophoric groups were generated during the aging process. The tensile shear strength of Single lap shear specimens increased firstly,and then decreased as exposed time increases. The samples occurred post cure during the process influced by UV radiation and temperature, and then the samples degraded, the micro morphology of specimens cracked heavily.Under O₃/T/P comprehensive environmental exposure, the color difference and yellowness index increased gradually as aging time increases. The area of methyl/methylene and ether linkage decreased gradually as aging time increases, while the area of carbonyl increased gradually. The tensile shear strength of Single lap shear specimens increased firstly, and then decreased as exposed time increases. The degree of aging obviously lower than that under UV/O₃/T/P comprehensive environmental.UV radiation is the main factor induced the degradation of epoxy adhesive, the antioxidant and composite additive can restrain the degradation of E-51 epoxy adhesives samples in to a certain degree, the composite additive is superior to the antioxidant underUV/O₃/T/P comprehensive environmental exposure, while the result is reverse under O₃/T/P comprehensive environmental exposure.