Analysis of Drying Process for Polymer Film

聚合物溶液加热空气干燥薄膜的工艺被用于各种聚合物薄膜的生产。该装置的设计和最佳操作条件的确定仅凭经验。本研究从两个方面对这一过程进行了分析：1)利用吸附实验得到的空气中溶剂蒸汽压与膜中溶剂浓度之间的平衡数据和相互扩散系数，对平板扩散方程进行了同时数值模拟。(1)聚氯乙烯-四氢呋喃体系，在工业装置…中进行恒定风温和当量时变风温条件下的间歇干燥实验更多。数值计算模拟结果较好地再现了实验干燥历程。膜内气泡产生的原因是1)溶剂的沸腾和/或2)膜底部的空气膨胀，(2)聚酰亚胺-DMAc体系，用Kapton和Upiex-S的聚酰亚胺聚合物溶液进行了干燥实验。两种聚合物均未检测到催化剂加速亚胺反应对干燥速度的影响。Kapton的干燥速率大于UPILEX-S。催化剂对有干燥历史的薄膜弹性模量的影响不明显。本资助研究的内容包括：1)利用间歇干燥实验装置研究了6-尼龙颗粒的干燥行为；2)提出了一种新的浓度相关的吸附实验扩散系数计算方法。较少

The drying process of film from polymer solution by heated air are used for the production of various polymer film. Design of the apparatus and determination of optimum operating conditions are carried out only through experiences. In this research, the analyses of the process were performed by two ways : 1) The theoretical simulation by simultaneous numerical solution of the diffusion equation for a slab with the data of equilibrium between vapour pressure of solvent in air and concentration of solvent in film and the mutual diffusion coefficient which were obtained from the sorption experiments. 2) The drying experiments using the batch drying experimental apparatus which can simulate the drying histories of film in commercial apparatus by programmed control of the heating air temperature.(1) Polyvinylchloride-THF system.The batch drying experiments were carried out for both the constant air temperatures and the equivalent time changes of the air temperature in a commercial apparatus … More . The simulation results by the numerical calculations presented the experimental drying histories satisfactorily. The causes of appearance of bubbles in film were 1) boiling of solvent and/or 2) expansion of air included in bottom of film.(2) Polyimide-DMAc system.The drying experiments were carried out for the solutions of DMAc with polyimide polymers of Kapton and Upilex-S. The effect of acceralation of imidization reaction by catalyst on the drying rate was not detected clearly for both polymers. The drying rate for Kapton was larger than that for Upilex-S. The effect of the catalyst on the elastic modulus of the films with a drying histories were not detected clearly. The lower values of elastic modulus was obtained for Kapton.The others investigated by this grant-in-aid are 1) the drying behaviour of 6-Nylon pellet using the batch drying experimental apparatus and 2) the proposal of a novel calculation method of concentration dependent diffusion coefficient on sorption experiment. Less