Effect of Temperature on Tensile Curve of Polyaspartic Ester Polyurea and Its Activation Energy Analysis

Abstract

Abstract The influence of ambient temperature on the tensile stress-strain curve of polyaspartic ester polyurea (PAE-PU) was investigated to discuss the yield and breakage mechanism of tensile deformation. Temperature has a significant effect on the tensile stress-strain curve of PAE-PU. At low temperature (27, 40 °C), it shows obvious yield and forced high elasticity. After the temperature exceeds 80 °C, the yield phenomenon disappears and shows high elasticity of rubber: the strain energy and breakage energy are significantly reduced. The yield activation energy of PAE-PU was calculated by yield strain time at different temperatures. It was found that the yield activation energy decreased with the increase of tensile rate. When the tensile rate is 500mm/min, among the activation energies calculated by breakage strength, yield strength and Young’s modulus at different temperatures, the ordinary elastic deformation activation energy is higher, while the yield and breakage activation energy are close and lower. The latter two are close to the hydrogen bond energy and one order of magnitude lower than the chemical bond energy of molecular chain.