Instrumentation of New Device to Estimate Gas Permeability and Viscoelastic Properties for Thin Polymeric Membranes Using Quartz crystal Osillator

在这项研究中，我们试图利用石英晶体振荡器原位估计聚合物膜的气体吸附和扩散特性以及粘弹性。石英晶体微天平QCM是一种非常灵敏的测量仪器，因为其振荡频率随电极上重量的变化而急剧变化。用QCM装置测得的CO_2吸附等温线与电子微天平法测得的数据完全吻合，该装置具有测量压力较高、只需少量样品(约30微克)等优点。此外，这种QCM方法还可以测量有机蒸气的吸附。测定了涂在QCM电极上的玻璃聚合物膜样品在60atm以下的CO_2吸附等温线。得到的吸附等温线可分为沿压力轴凹陷的玻璃区和线性的橡胶区两部分。拐点…等温线的进一步裂解被认为是CO_2吸附增塑所致的等温玻璃化转变点。接下来，我们尝试测量硅橡胶的CO_2吸附等温线和CO_2渗透系数。在CO_2的临界压力下，溶液的溶解度和渗透率都发生了变化。从这些结果可以看出，CO_2对聚合物的渗透性能受CO_2的聚集程度的影响。另一方面，我们还测量了涂覆不同聚合物的石英晶体振荡器的谐振电阻。电阻在9 MHz的GRASS转变温度以上突然增大，该温度是由不同频率下的介电色散确定的一次色散温度计算得出的。聚合物涂层振荡器的谐振频率和电阻行为可以与聚合物的状态相对应，即在玻璃、橡胶、流体状态下。通过这些研究，我们可以证实聚合物涂层石英晶体振荡器在聚合物的吸附和粘弹性行为方面具有很高的潜力。较少

In this study, we try to estimate the gas sorption and diffusion properties and viscoelasticity of the polymeric membrane in situ using the quartz crystal oscillator. Quartz crystal microbalance, QCM is known to be very sensitive measuring device because the oscillating frequency changes sharply with the variation of weight on the electrode. The CO_2 sorption isotherm obtained by the QCM device was fully pverlapped with the data observed by the electromicrobalance method.This QCM device has some advantages, that is, it can measure up to comparatively high pressure and need only a few specimens (ca.30mug), and so on. Moreover, this QCM method could measure the sorption of organic vapors. The CO_2 sorption isotherms of the glassy polymer film specimen coated on QCM electrode was carried out up to 60 atm. The sorption isotherm obtained can be divided into two sections, the glassy region which is concave toward the pressure axis and the rubbery region which is linear. The inflection point … More splitting up the isotherm is considered the isothermal glass transition point caused by plasticizing by CO_2 sorption. Next, we try to measure the CO_2 sorption isotherms and CO_2 permeability coefficients for the silicone rubber. The solubility and permeability changed at the critical pressure of CO_2. From these results, it was considered that the permeation properties of CO_2 for polymers are influenced by the degree of aggregation of CO_2. On the other hand, we also measured the resonant resistance of the quartz crystal oscillator coated with various polymers. The resistance increased suddenly above the grass transition temperature at 9MHz which is calculated from the primary dispersion temperature determined by dielectric dispersion at various frequencies. The behaviors of resonant frequency and resistance of the polymer-coated oscillator could be corresponding to the state of the polymer, i.e, in glassy, rubbery, fluid states. From these study, we could confirm the high potential of the polymer-coated quartz crystal oscillator for the sorption and viscoelastic behaviors of polymers. Less