Stevenson J F, Parry J S, Gupta K M
J Biomed Mater Res. 1978 May;12(3):401-19. doi: 10.1002/jbm.820120312.
Two experimental methods have been developed to characterize the pressure-driven flow of a liquid through the walls of single hollow-fiber membranes. In one method, the permeation rate is measured directly by following the air-water interface in a pressurized pipet connected to a hollow fiber which is sealed at one end. With the second method, the permeation rate is determined by tracking the decent of an air bubble inside a pressurized hollow fiber sealed at one end. Results obtained by the two experimental methods are in good agreement. Darcy's law is used to analyze the experimental data because the Darcy permeability constant, k is an intrinsic property of the material. The membrane dimensions and the Darcy permeability constant for reconstituted collagen hollow fibers are shown to be quite sensitive to hydrogen ion concentration and ionic strength. A conceptual link between the Darcy permeability constant and the membrane microstructure is obtained by combining the the aligned-rod structural model for reconstituted collagen proposed by Kramer with a hydrodynamic calculation due to Happel and electrical double-layer theory. On the average, the predictions of this model for volume fraction solids and microstructure dimensions are in reasonable agreement with experimental observations.
已经开发出两种实验方法来表征液体通过单个中空纤维膜壁的压力驱动流动。在一种方法中，通过跟踪连接到一端密封的中空纤维的加压移液管中的空气 - 水界面来直接测量渗透速率。在第二种方法中，通过跟踪一端密封的加压中空纤维内气泡的下降来确定渗透速率。两种实验方法获得的结果吻合良好。由于达西渗透常数k是材料的固有属性，因此使用达西定律来分析实验数据。结果表明，重构胶原中空纤维的膜尺寸和达西渗透常数对氢离子浓度和离子强度相当敏感。通过将Kramer提出的重构胶原的排列棒结构模型与Happel的流体动力学计算和电双层理论相结合，获得了达西渗透常数与膜微观结构之间的概念联系。平均而言，该模型对固体体积分数和微观结构尺寸的预测与实验观察结果合理吻合。
