縦波による高分子溶液の緩和現象 (II)
1971 年 20 巻 212 号 p. 675-680
詳細
1971 年 20 巻 212 号 p. 675-680
The Ultrasonic absorption of Polyvinylacetate in acetone solution was measured by the pulse method over 5MHz-75MHz within the temperature range from 0°C to 20°. A thermal relaxation phenomenon was observed in this frequency range.
A rotationary isomer model has been presented based on the observed molecular weight dependence of compressibility at 1MHz. This model is composed of head-to-tail sequences of polymer chain bonds and involves a doubly degenerated ground state.
The energy state in this model is found to be
ΔH0=1.5±0.5Kcal/mol
ΔH≠=4.8Kcal/mol.
