Dielectric relaxation parameters of Isopropyl acetate (IPA)-xylene mixtures with different concentrations and temperatures have been measured in the frequency range of 10 MHz to 30 GHz using time domain reflectometry technique. Static dielectric constant, relaxation time, excess permittivity, excess relaxation time, Bruggeman factor, Kirkwood correlation factor and thermodynamic parameters have been determined to understand molecular association between the IPA and xylene molecules. For entire concentrations of IPA-xylene mixture the Kirkwood correlation factor is less than one which shows the antiparallel nature of electric dipole orientation. The experimental values of dielectric constant obtained from time domain reflectometry are in well agreement with theoretical values of dielectric constant obtained by Luzar model. Positive values of enthalpy and entropy indicating that the system is endothermic and less ordered while Gibbs free energy decreases with increase of IPA in xylene.

中文翻译：

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介电弛豫法研究乙酸异丙酯-二甲苯混合物的分子相互作用

使用时域反射技术，已在10 MHz至30 GHz的频率范围内测量了不同浓度和温度的乙酸异丙酯（IPA）-二甲苯混合物的介电弛豫参数。确定静态介电常数，弛豫时间，过量介电常数，过量弛豫时间，Bruggeman因子，Kirkwood相关因子和热力学参数，以了解IPA和二甲苯分子之间的分子缔合。对于IPA-二甲苯混合物的整个浓度，柯克伍德相关因子小于1，这表明电偶极子取向具有反平行性。从时域反射法获得的介电常数的实验值与通过Luzar模型获得的介电常数的理论值非常吻合。