Ionic Polyimides: Design, Synthesis, Characterization and Modeling of a Versatile Material Platform for Membrane Separations

建议编号：1605411，PI：BARA，J.E.TITLE：将先进的聚合物材料作为高效节能气体分离的膜工程气体分离，如空气分离(氧气/氮气)、天然气中的二氧化碳/甲烷和合成气(氢气/一氧化碳)是工业化学过程的重要组成部分，这些过程产生对国家经济和福祉至关重要的许多最重要的经济材料。传统上，这些分离是使用成熟的、但能源密集型的操作进行的，如蒸馏或吸收和汽提过程。聚合物膜的使用提供了另一种方法，以节能的方式和较低的投资成本执行这些分离。然而，仍然存在空白，阻碍了聚合物膜技术的更广泛使用。该项目将提供必要的基础研究，以了解聚合物结构和化学对性能属性的作用，如提高产量、提高产品纯度和延长膜寿命。通过使用合成化学、聚合物工程和计算机模拟，该项目将把不同类别的聚合物材料中最重要的结构元素组合成独特的、史无前例的聚合物结构，这些结构具有每种材料的理想性能，同时旨在消除或尽量减少各自的限制。对该项目中正在开发的新聚合物的研究将打开一个巨大的新材料库，用于各种工程应用。此外，正在使用的计算机模拟将促进研究人员在分子水平上可视化和理解聚合物材料的方式。该项目将培养研究生和本科生在协同的实验和计算环境中工作，这是21世纪研究的一个重要方面。该项目还将涉及以3D打印和智能手机移动应用程序为中心的外联活动，以向更广泛的学生介绍工程概念，使用他们熟悉的工具和游戏。这项研究的主要目标是通过实验和计算了解用于气体分离的离子聚酰亚胺聚合物膜的结构-性能-性能关系。这项工作将评估离子聚酰亚胺在与能源生产和温室气体排放有关的几个关键气体对中的效用。通过结合聚酰亚胺、离子液体、具有固有微孔性的聚合物和用于金属有机骨架的配体的元素，离子聚酰亚胺的设计策略完全是未知的，并提供了控制和改善聚合物性能的能力，例如基于库仑引力驱动的非共价超分子组装的分数自由体积(FFV)，这也可能有助于减缓/阻止聚合物老化。随着独特的分子水平模拟模型的发展，对离子聚酰亚胺性能的基本了解将得到加强。将采用三种不同水平的模型分辨率(量子力学、分子动力学和动力学蒙特卡罗)，以建立具有显式气体/聚合物/气体界面的综合膜模型。这将使模型场向实验系统的真实表示更近一步，允许描述梯度驱动流，类似于与实际工业气体分离过程相关联的压降环境。该项目的成功将转化为制造纳米结构聚合物膜的能力的重大进步，以实现更低的能源和成本分离。此外，基于传统聚酰亚胺作为高性能聚合物众所周知的广泛用途，离子聚酰亚胺很可能在许多其他应用中也是可取的。

Proposal Number: 1605411, PI: Bara, J.E.Title: Engineering Advanced Polymer Materials as Membranes for Energy Efficient Gas SeparationsGas separations such as air separation (oxygen/nitrogen), carbon dioxide/methane in natural gas, and syngas (hydrogen/carbon monoxide) are important components of industrial chemical processes that produce many of the most economically important materials vital for the Nation's economy and well being. Traditionally, these separations have been carried out using well-established, but energy intensive operations such as distillation or absorption and stripping processes. Use of polymer membranes offers an alternative approach to perform these separations in an energy efficient manner and with lower investment cost. However, gaps still exist that block the wider use of polymer membranes technologies. This project will provide the fundamental research that is needed to understand the role of polymer structure and chemistry on performance attributes such as enhanced throughput, increased product purity and long membrane lifetimes. Through the use of synthetic chemistry, polymer engineering, and computer modeling, this project will combine the most important structural elements from the separate classes of polymer materials into unique and unprecedented polymer structures that possess the desirable properties of each individual material while aiming to eliminate or minimize the respective limitations. Investigation of the new polymers being developed in this project will open a vast new library of materials for use in a variety of engineering applications. Furthermore, the computer simulations being employed will advance the ways in which researchers visualize and understand polymeric materials at the molecular level. This project will train graduate and undergraduate students to work in a synergistic experimental and computational environment, an important aspect of 21st century research. This project will also involve outreach activities centered around 3-D printing and mobile apps for smartphones to inform a wider range of students on concepts in engineering using tools and games that they are familiar with.The key objectives of this research are to experimentally and computationally understand the structure-property-performance relationships underlying ionic polyimide polymer membranes for gas separations. This work will assess the utility of ionic polyimides across several key gas pairs related to energy production and greenhouse gas emissions. By combining elements of polyimides, ionic liquids, polymers of intrinsic microporosity and ligands used in metal organic frameworks, the ionic polyimide design strategy is completely unexplored and provides the ability to control and improve polymer properties such as fractional free volume (FFV) based on non-covalent supramolecular assembly driven by coulombic attractions, which may also assist in slowing/stopping polymer aging. The fundamental understanding of ionic polyimide performance will be enhanced with the development of unique molecular-level simulation models. Three different levels of model resolution will be employed (quantum mechanics, molecular dynamics, and kinetic Monte Carlo) in order to build a comprehensive membrane model with explicit gas/polymer/gas interfaces. This will move the modeling field a significant step closer towards realistic representations of the experimental systems, allowing the description of gradient-driven flow, similar to the pressure-drop environment associated with actual industrial gas separation processes. The success of this project will translate to major advancements in the ability to build nanostructured polymer membranes, for lower energy and cost separations. Furthermore, ionic polyimides are likely to be desirable for many other applications based on the well-known broad utility of conventional polyimides as high-performance polymers.