抄録
This paper is concerned with the mechanical and optical characterization of epoxy resin for practical photoviscoelastic analysis. The birefringence and stress are measured under various constant strain-rates at various constant temperatures. The results obtained are summarized as follows: (1) The epoxy resin used has a strong time and temperature dependence upon mechanical and optical properties. Using thermo-rheologically simple properties, the master curves of relaxation modulus Er and relaxation birefringence-strain coefficient C∈·rcan be obtained. (2) The time-temperature shift factor of Er coincides well with that of C∈·r and they are approximated with two Arrhenius'equations having different activations energies. (3) The temperature correction according to the theory of rubbery elasticity can be omitted when the master curve of Er is obtained. (4) The inverse relaxation stress-birefringence coefficient and the inverse creep strain-birefringence coefficient, which are necessary for practical photoviscoelastic analysis, are calculated using the master curves of Er and C∈·r· Based on this calculation, the convenient approximation by Knauss can be applied with estimating the error of approximation from the slope of curves of Er and C∈·r·
