Layer-by-layer polymer assemblies as size-selective gas separation membranes

作为尺寸选择性气体分离膜的层层聚合物组件

• 批准号: 1403686
• 负责人: Benjamin Wilhite
• 金额: $ 30万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-15 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1403686&HistoricalAwards=false
• 关键词: Layer; layer; polymer; assemblies; size

1403686WilhiteTexas Engineering Experiment StationThe proposed research effort addresses the need for low-cost membrane materials for gas purification by investigating polymer coatings capable of combining high rates of gas separation with high purity. The researchers propose growing polymer films one layer at a time by alternately dipping the membrane substrate into a water bath containing positively- and negatively-charged polymers. This results in the growth of a Layer-by-Layer (LbL) thin film. Recently the PIs have confirmed that order-of-magnitude improvements in hydrogen-carbon dioxide and hydrogen-nitrogen selectivity may be achieved using LbL films assembled from polyacrylic acid (PAA) and branched polyethylemine (PEI) solutions. The proposed work leverages these recent results to identify breakthrough polymeric materials capable of size-selective gas separations to meet multiple sustainable energy needs. The PIs propose to use the LbL assembly technique to manipulate membrane structure, in turn tuning both transport properties and membrane durability. Increased transport properties and membrane durability will be achieved through a combination of (i) fundamental materials analysis aimed at characterizing the extent of polyanion and polycation bonding and relating it to mechanical and nanostructural properties, and (ii) transient gas permeation measurements for obtaining precise measurements of individual gas permeabilities through the LbL membrane. The research efforts are focused not only upon proven hydrogen-carbon dioxide separation capability of LbL films, but also applying fundamental concepts to tailored membranes for biofuel (ethanol) dehydration and natural gas processing. Therefore, materials developed may have significant and immediate impact upon the energy industry. The PI's team has ongoing engagement of underrepresented groups at the graduate and undergraduate levels in socially relevant research topics. Aspects of this work will also be incorporated into multiple ongoing K-12 outreach programs present at Texas A&M University. The PI team plan to also develop online learning exercises utilizing the popular line of HexBug Nano toys, which will be disseminated online. These outreach efforts will be leveraged as a platform for developing teaching tools for illustrating diffusion and related transport phenomena concepts to non-STEM audiences.

1403686 WilhiteTexas工程实验站拟议的研究工作通过研究能够将高速率气体分离与高纯度相结合的聚合物涂层，解决了对用于气体净化的低成本膜材料的需求。研究人员提出，通过将膜基材交替浸入含有正电荷和负电荷聚合物的水浴中，一次生长一层聚合物膜。这导致逐层（LbL）薄膜的生长。最近PI已经证实，使用由聚丙烯酸（PAA）和支链聚乙烯亚胺（PEI）溶液组装的LbL膜可以实现氢-二氧化碳和氢-氮选择性的数量级改进。拟议的工作利用这些最近的结果来确定能够进行尺寸选择性气体分离的突破性聚合物材料，以满足多种可持续能源需求。PI建议使用LbL组装技术来操纵膜结构，进而调节传输特性和膜耐久性。增加的传输性能和膜的耐久性将通过以下的组合来实现：（i）旨在表征聚阴离子和聚阳离子键合的程度并将其与机械和纳米结构性能相关联的基本材料分析，以及（ii）用于获得通过LbL膜的单个气体渗透率的精确测量的瞬态气体渗透测量。研究工作不仅集中在LbL膜的氢-二氧化碳分离能力上，而且还将基本概念应用于生物燃料（乙醇）脱水和天然气加工的定制膜。因此，开发的材料可能对能源行业产生重大和直接的影响。PI的团队在研究生和本科生阶段持续参与代表性不足的群体参与社会相关的研究课题。这项工作的各个方面也将纳入目前在德克萨斯州A M大学正在进行的多个K-12外展计划。PI团队还计划利用流行的HexBug Nano玩具系列开发在线学习练习，并将在网上传播。这些推广工作将作为开发教学工具的平台，用于向非STEM受众说明传播和相关运输现象概念。