• Da Silva, Lfm
• Lopes, Am
• Marques, Eas
• Carbas, Rjc

Abstract

This paper describes the influence of the curing temperature on the physical and mechanical properties of three structural adhesives. This work was undertaken to improve the understanding of the effect of curing temperature in the glass transition temperature, T-g, and stiffness of epoxy adhesives. The mechanical properties (Young's modulus and yield strength) of the adhesives were measured in bulk specimens. T-g was measured by a dynamic mechanical analysis using an in-house developed apparatus. The curing process was the same for all tests, consisting of a curing stage followed by a post cure stage. The initial stage was performed at different temperatures. T-g and the mechanical properties was found to vary as a function of the cure temperature of the adhesive. When cured below the cure temperature, T-cure, at which the T-g of the fully cured network, T-g , is achieved, the strength and stiffness of the adhesive increase as the cure temperature increases and the T-g is higher than the cure temperature. When cured above the T-cure at which the T-g is achieved, the strength and stiffness decrease as the cure temperature increases and the T-g is higher than the cure temperature.

Topics

• impedance spectroscopy
• glass
• glass
• strength
• glass transition temperature
• yield strength
• curing
• dynamic mechanical analysis