Industry/University Cooperative Research: A Study of Small Molecule Transport in Polymers by Oscillatory Sorption (Supplement)

研究综述：用振荡吸附技术研究聚合物/渗透剂体系中的非经典互扩散。研究中使用的物理体系是聚苯乙烯(PS)/乙苯(EB)和聚酰亚胺(PI)/N-甲基吡咯烷酮(NMP)，它们被选为典型的两大类行为。将进行一系列实验，改变控制聚合物扩散行为的重要无量纲参数：扩散Deborah数(DEB)。研究人员的目标是观察随着DEB的减少，从非经典行为到经典行为的转变。我们将与一种新的热流变学理论进行定量比较。独特性/创新：研究人员建议使用Vrentas和Duda(J Memb.SCI。18,161(1984))。这种方法可能很强大：它对相互扩散的描述类似于通过动态机械测试来描述动量传输。它消除了与不精确的初始条件相关的不确定性，并允许精确地操纵观察的时间尺度。该设计采用了压电式石英晶体换能器。该理论方法结合了现代的非平衡热力学和浓缩聚合物溶液的动力学理论；它使Brochard和DeGennes(Phys.化学。海德。4313(1982))。在这种新的方法中，没有可调整的常数，因此可以获得数据的先验、定量预测并进行检验。技术影响/意义：拟议的实验将阐明在小驱动力下非经典效应的分子起源。理论的成功应用将代表着对非经典运输的第一次严格预测。然后，这项工作可以扩展到揭示管理非线性运输的更一般的规律。这项研究也有几个实际的好处：(A)最终，该理论将允许从标准流变学数据和经典扩散数据进行非经典扩散速率的工程预测；(B)石英晶体微天平使研究聚合物薄膜和涂层中的小分子传输成为可能，(C)仔细研究PI/NMP体系中的传输对于电子工业具有普遍意义。

Research Summary: Non-classical mutual diffusion in polymer/penetrant systems is studied by an oscillatory sorption technique. The physical systems used in the study are polystyrene (PS)/ethylbenzene (EB) and polyimide (PI)/n-methyl pyrrolidone (NMP), and they are chosen because they are typical of 2 broad classes of behavior. A series of experiments will be performed varying the important dimensionless parameter governing the polymer diffusion behavior: the diffusion Deborah number (DEB). The researchers aim to observe the transition from non- classical to classical behavior as DEB is decreased. Quantitative comparisons with a new, thermo-rheological theory will be made. Uniqueness/Innovation: The researchers propose to use the oscillatory sorption technique for macromolecular systems advocated by Vrentas and Duda (J Memb. Sci. 18, 161 (1984)). The method is potentially powerful: its characterization of mutual diffusion resembles that of momentum transport by dynamic mechanical testing. It eliminates uncertainties connected with imprecise initial conditions and allows precise manipulation of the time scale for observation. The proposed design employs a piezoelectric quartz crystal transducer. The theoretical approach combines modern, non-equilibrium thermodynamics and kinetic theory of concentrated polymer solutions; it formalizes the intuitive developmentof Brochard and DeGennes (Phys. Chem. Hyd. 4, 313 (1982)). There are no adjustable constants in this new approach so that a priori, quantitative predictions of the data can be obtained and tested. Technical Impact/Significance: The proposed experiments will clarify the molecular origins of non-classical effects at small driving forces. Successful application of theory will represent the first, rigorous predictions of non-classical transport. The work can then be extended to expose more general laws governing nonlinear transport. The research has also several practical benefits: (a) ultimately the theory will allow engineering predictions of non-classical diffusion rates from standard rheological data and classical diffusion data; (b) the quartz crystal microbalance enables the study of micromolecule transport in polymer thin film and coatings development, (c) careful research of transport in the PI/NMP system is of generic importance to the electronics industry.