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Cosolvent effects in polymer-solvent systems.

机译：聚合物-溶剂体系中的助溶剂作用。

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Devolatilization of polymers is important to industrial applications such as film drying, foam production, microelectronics manufacturing, and bulk plastics processing. The mass transport and thermodynamics within such systems often limits production throughput. For example, a common method of foam devolatilization is ambient pressure desorption. In this situation, the diffusion of residual species from the foam to the surrounding air is the limiting step in the manufacturing process. Therefore, the use of a cosolvent to affect the solubility and diffusion favorably is an area of interest to industry. However, little data exist and few models are capable of predicting the influences that occur when a cosolvent is added to a system.; This thesis focuses on measuring and describing cosolvent effects in polymer-solvent systems. Inverse gas chromatography was used to test the influence of CO2 and ethylene at high pressures on the solubility and diffusion of several solvents in poly(vinyl acetate) and poly(styrene). Through testing at multiple conditions it was possible to determine which gas had the largest effect on the polymer-solvent behavior. In addition, influences due to solvent size were examined.; A ternary experiment was designed to probe the effect of water on the solubility and diffusivity in a poly(ethylene)-ethylene system. The experiment is a simple gravimetric technique for measuring mass uptake of penetrants in polymers.; Lastly, several thermodynamic models are applied to a phase equilibria problem of predicting anomalous solubility behavior in copolymer systems. In certain systems, solvents have been observed to have higher solubility in copolymers compared to the two respective homopolymers. The goal was to determine which, if any, models could predict such behavior without experimental data for parameterization.
机译：聚合物的脱挥发分对工业应用非常重要，例如膜干燥，泡沫生产，微电子制造和块状塑料加工。这种系统中的传质和热力学常常限制了生产量。例如，泡沫脱挥发分的常用方法是环境压力解吸。在这种情况下，残留物质从泡沫扩散到周围空气中是制造过程中的限制步骤。因此，使用助溶剂有利地影响溶解度和扩散是工业上关注的领域。但是，几乎没有数据，很少有模型能够预测将助溶剂添加到系统中时发生的影响。本文主要研究和描述聚合物-溶剂体系中助溶剂的作用。反相气相色谱法用于测试高压下的CO2和乙烯对几种溶剂在聚乙酸乙烯酯和聚苯乙烯中的溶解度和扩散的影响。通过在多种条件下进行测试，可以确定哪种气体对聚合物-溶剂行为的影响最大。另外，检查了由于溶剂尺寸引起的影响。设计了三元实验，以探讨水对聚乙烯（乙烯）-乙烯系统中溶解度和扩散率的影响。该实验是一种简单的重量技术，用于测量聚合物中渗透剂的质量吸收。最后，将几种热力学模型应用于预测共聚物体系中异常溶解行为的相平衡问题。在某些系统中，与两种均聚物相比，已观察到溶剂在共聚物中具有更高的溶解度。目的是确定哪些模型（如果有的话）可以在没有用于参数化的实验数据的情况下预测此类行为。

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