ポリエチレンオキシドの溶液物性

概要

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The dipole moments of monodisperse polyethylene oxide) (PEO) were determined from dielectric constant and density measurements performed on their dilute benzene solutions over the temperature range from 25 to 55℃. PEO samples of seven different molecular weights (MJ ranging from 2.1 ×104 to 86 × 10^4 were used. The observed values of average dipole moment per structural unit (μ) at 25℃ were as follows, 1.046^5D(M_w = 2.1 × 104), 1.037_2D(M_w = 4.6 × 10^4), 1.039_3D(M_w) = 9.5 × 10^4), 1.040_5D(M_w = 17 × 1.04), 1.037_7D(M_w = 27× 104), 1.040_8D(M_w = 57 × 10^4) and 1.042_1D(M_w = 86 × 10^4) (D; debye unit). These values of μ are nearly equal with each other and response of μ to the molecular weight is not observed, which indicates that the dipole moment of poly(ethylene oxide) is not influenced by the excluded volume effect. The averaged dipole moment ratio was <μ^2>/nm^2 = 0.472±0.002 (25℃) for six polymer samples except for M_w = 2.1 × 10^4 and the temperature coefficient averaged for seven polymer samples was d ln<μ^2>/dT = (2.01±0.29) × 10^<-3> K^<-1>.
東京女子大学の論文
2001-03-05