抄録
Thermally stimulated current (TSC) of blends of styrene-acrylonitrile copolymer (SAN) and poly(methyl methacrylate) (PMMA) having various ratios in miscible state has been investigated. The blends were prepared by the solvent casting method, and removal of residual solvent was carefully confirmed. The thin film having exactly same thickness and contact area attached to electrodes was used, and thermally stimulated depolalization current (TSDC) was detected. The thin blend film was polarized at 110 °C for 30 min under 100 V⁄mm, cooled down to -130 °C, and then the depolalized current was measured by heating at a rate of 7 °C⁄min to 110 °C. The α peak temperature was located below the temperature expected from the additive rule as a function of PMMA content. The integrated area of the α peak of TSDC was plotted as a function of PMMA content, giving also the strong negative tendency that the α peak temperature is located below the temperature expected from the additive rule. These TSC results were interpreted by the idea that the acrylonitrile groups having strong dipole moment were interacted with the methacrylate groups in the miscible state, resulting in diminishing the polar capacity.
