水基流延成型的膜带在干燥技术的许多方面存在着“知其然而不知其所以然”,其干燥过程在固体介质中同时发生热量、质量和动量的传递,用数学对其进行描述存在着相当的困难性和无效性.可以将流延膜的干燥过程分为恒定速率阶段和蒸发速率下降两个阶段.过去由于实验技术条件的限制使人们对一些干燥机理没有充分的认识,就是研究较多的干燥动力学,也存在禁地和误区.由于干燥机理复杂,目前研究得不够充分,关于干燥的动力学数据多取自试验测定值.通过结构与性能关联的研究可拓展人们对于燥过程的认识:通过电子显微镜对膜带的表征,可深入研究其显微结构及湿组份在膜带内的运动机理；通过热重分析技术将膜带的湿度变化与其温度变化相关联,可为设计干燥工艺提供合理的依据；通过固相核磁共振技术,测量湿组份中水分子层的质子自旋松弛时间,可用来半定量计算膜带中的可除去结合水和自由水及不可除去结合水的比例.%Many issues of film drying for aqueous tape casting are to be accounted for. For example, the simultaneous transfer of heat, mass and momentum in solids is beyond the description of mathematics. The drying process of tape-cast films can be divided into a stage of drying at a constant speed and a stage of evaporating at a declining speed. In the past, due to the limitations in experimental technology, some drying mechanisms were not fully understood. There were even off-limits and fallacies in drying kinetics. As the drying mechanism is very complex and the present study was insufficient, the kinetic data of drying came from laboratory tests. The research on the relation between structure and properties can expand the understanding of the drying process: the characterization of the film by electron microscopy can reveal the change of microstructure and moisture component in it; the TGA technology associates the change in humidity of the film with temperature, thus providing a theoretical basis for the design of drying process; solid-state NMR spectroscopy can be used to measure the water-proton spin-lattice relaxation time of the moisture and to semi-quantitatively calculate the ratios of both the removable hydration and free water and the unremovable bound water.
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