Analysis of Drying Process for Polymer Film

利用加热空气将聚合物溶液干燥成薄膜的过程用于生产各种聚合物薄膜。设备的设计和最佳操作条件的确定只能通过经验进行。本研究从两个方面对该过程进行了分析：1）利用吸附实验得到的溶剂在空气中的蒸气压与膜中溶剂浓度的平衡数据和互扩散系数，通过对平板扩散方程的联立数值解进行了理论模拟; 2)干燥实验采用间歇式干燥实验装置，通过程序控制热风温度，可以模拟商业装置中薄膜的干燥历史。(1)聚氯乙烯-四氢呋喃（THF）体系的间歇干燥实验，在工业装置上进行了恒温和恒温等效时间变化的间歇干燥实验 ...更多信息 .数值计算的模拟结果较好地反映了实验干燥过程。在膜中出现气泡的原因是1）溶剂的沸腾和/或2）包含在膜底部的空气的膨胀。(2)聚酰亚胺-DMAc体系，对DMAc与Kapton和Upilex-S聚酰亚胺聚合物的溶液进行了干燥实验。催化剂加速亚胺化反应对两种聚合物干燥速率的影响均不明显。Kapton的干燥速率大于Upilex-S。催化剂对具有干燥历史的膜的弹性模量的影响没有被清楚地检测到。Kapton的弹性模量值较低。本资助项目还研究了6-Nylon颗粒在间歇干燥实验装置上的干燥行为和吸附实验中浓度相关扩散系数的新计算方法。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