Structure Control in Membrane Formation

摘要：本项目旨在通过理论/模拟和实验研究，了解膜形成过程中铸造后条件（即凝固、提取和干燥）对微孔和纳米孔膜结构的影响。该研究将是第一个将膜形成过程的凝固、交换和干燥步骤与膜形态（细胞的大小和大小分布以及连接细胞的孔隙）联系起来的系统和基础研究。这种关系将通过基于材料科学、输运现象和表面现象的基本概念的模拟的发展来建立。待开发的模拟将描述后期或后粗化过程的敏感性，从而使制造商能够将材料结构和性能与材料形成过程联系起来。这些过程的计算机模拟将允许对不同的处理条件、稀释剂和萃取剂进行调查，而无需进行广泛而昂贵的实验室研究。从本研究中获得的基本知识将适用于非溶剂诱导相分离和热诱导相分离的膜形成过程。所提出的研究将对应用产生重大影响，其中良好控制的结构对分离和选择性很重要。例如，在电池分离器、膜蒸馏应用和血液透析中需要严格控制的形态是有充分记录的。具体来说，这些应用需要具有更窄孔径分布和更高孔隙率的膜。通过裁剪膜的形态，渗透性，排斥和选择性，可以优化分离应用。这在生化、制药和生物医学分离中尤为重要。例如，分子生物学领域的最新进展增加了以大分子量蛋白质和肽为基础的药物的可用性，从而提供了治疗许多疾病的新方法。这些新型生物药物的结构、物理化学性质、稳定性、药效学和药代动力学对它们在加工过程中的分离方式和进入人体的方式提出了严格的要求。适当控制用于分离或回收这些药物的膜的细胞和孔径，以及用于递送的载体，可能会产生显著的有益影响。PI过去与工业实验室合作研究的记录将有助于在拟议研究中获得的知识的转移。广泛的影响将是显著的，良好控制的膜孔结构可以影响各种分离应用的膜设计。因此，改进的控制孔径分布的方法可以在许多行业中提供有益的效果。

Abstract Proposal Title:Structure Control In Membrane Formation, Proposal Number: CTS-0625233, Principal Investigator:Douglas R. Lloyd, Institution: University of Texas at AustinAbstract:This project aims to understand effects of post casting conditions during membrane formation (i.e., solidification, extraction, and drying) on structures of microporous and nanoporous membranes using theoretical/simulational and experimental investigations. The proposed research will be the first systematic and fundamental study to relate the solidification, exchange, and drying steps of the membrane formation process to the membranemorphology (size and size distribution of the cells and the pores connecting the cells). This relationship will be established through the development of simulations based on fundamental concepts of materials science, transport phenomena, and surface phenomena. The simulations to be developed will describe the sensitivities of the late-stage or post-coarsening processes and thereby allow manufacturers to relate material structure and performance to the material formation process. Computer simulation of the processes will allow investigation into differentprocessing conditions, diluents, and extractants without extensive and expensive laboratory research. The fundamental knowledge gained from this research will be applicable to membrane formation process that involves nonsolvent-induced phase separation as well as thermally induced phase separation.The proposed research will have a major impact in applications where a well-controlled structure is important for separation and selectivity. For example, the need for tightly controlled morphologies in battery separators, membrane distillation applications, and hemo-dialysis is well documented. Specifically, these applications need membranes with narrower pore size distributions and higher porosities. By tailoring the morphology of membranes, permeability, rejection, and selectivity, can be optimized for separations applications. This is particularly important in biochemical, pharmaceutical and biomedical separations. For example, recent advances in the field of molecular biology have increased availability of large molecular weight protein- and peptide-based drugs, and thus new ways to treat a number of diseases. The structure, physicochemical properties, stability, pharmacodynamics, and pharmacokinetics of these new biopharmaceuticals place stringent demands on the way they are separated during processing and the way in which they are delivered into the body. Proper control of cell and pore size in embranes used for the separation or recovery of these drugs, as well as the carriers used for delivery, could have significant beneficial impact. The PI's past record of collaborative research with industrial laboratories will facilitate the transfer of the knowledge gained in the proposed research. Broad impact will be significant where well-controlled membrane pore structure can affect membrane design for a variety of separation applications. Therefore, improved method of controlling pore size distribution can provide beneficial results in many industries.