CAREER: Engineering polymers cohesive energy density and free volume for highly selective organic separations

职业：工程聚合物内聚能密度和自由体积，用于高选择性有机分离

• 批准号: 2043648
• 负责人: Michele Galizia
• 金额: $ 54.36万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2043648&HistoricalAwards=false
• 关键词: CAREER; Engineering; polymers; cohesive; energy

About 10% of global energy consumption (7.5 GJ per person every year) is devoted to chemical separations. Enhancing the energy efficiency of industrial separations is crucial to decrease costs and control environmental pollution. Solutes are typically separated from the organic solvents in which they were synthesized using energy intensive separations such as distillation and absorption. Polymer membranes can be used in substitution of or in conjunction with traditional technologies to separate species based on their permeability through the membrane material. However, new methods for controlling the selectivity and lifetime of polymer membranes are urgently needed to make membrane-based separations economically competitive. This project will develop a new approach to engineer selectivity by acting on the membrane material properties (cohesive energy density) and morphology (free volume architecture). Designing materials that exhibit high cohesive energy density is expected to enhance the capability of a membrane to separate molecules based on their different solubilities, and incorporating functional groups that provide a more uniform and permanent free volume is expected to enhance the ability to separate molecules based on their size. The combination of high cohesive energy density and proper free volume architecture will yield polymer membranes exhibiting previously unattainable selectivity for organic separations. This CAREER project will combine experimental and computational approaches to discover a new class of materials prepared by blending commercial and novel polymers. These blended polymers will be judiciously selected to exhibit high cohesive energy density and have porous networks exhibiting non-collapsible free volume architecture. The structure of these materials will be systematically tuned to maximize the selectivity for target species while guaranteeing superior long-term stability. Equally important, this CAREER project will promote discovery-based learning for high school, undergraduate, graduate students, their families, and the general public. Results from this project will be disseminated directly in the classroom, through workshops and high-school educational modules to enhance public science and engineering literacy, and via influential conference talks and publications in scientific journals.Conventional approaches to tailor selectivity in polymer membranes are often ineffective. The scientific goal of this CAREER project is to discover, synthesize, and understand next-generation polymer membranes for organic solvent reverse osmosis and nanofiltration. The leit motif of cohesive energy density and configurational free volume will be leveraged in the design of these high selectivity membranes with enhanced long-term stability. The fundamental hypothesis is that a polymer membrane's solubility-selectivity concomitantly increases with increasing cohesive energy density, and that diffusivity-selectivity systematically increases via the incorporation of iptycene moieties that confer non-collapsible configurational free volume. Using a combined experimental and theoretical approach to test these hypotheses, this project will lead to highly selective and stable polymer membranes for organic separations and will enrich the fundamental understanding of structure-property correlations for membrane-based organic separations. This interdisciplinary research program will exploit materials discovery, synthesis, characterization, and modeling as a vehicle to educate diverse student populations at various levels and enhance science and engineering literacy among the general public. Research and education will be integrated via i) an educational module for middle and high school students in the Norman, OK area, ii) an Advanced Polymers Workshop in the Southwest region of the US, iii) a new course offering for chemical engineering students at the University of Oklahoma, and iv) interdisciplinary training opportunities for a population of diverse graduate, undergraduate and middle/high school students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

全球约10%的能源消耗(每人每年7.5GJ)用于化学分离。提高工业分离的能效对于降低成本和控制环境污染至关重要。溶质通常通过蒸馏和吸收等能量密集型分离方法从合成溶质的有机溶剂中分离出来。聚合物膜可用于替代传统技术，或与传统技术结合使用，以根据其透过膜材料的渗透性来分离物种。然而，迫切需要新的方法来控制聚合物膜的选择性和寿命，以使基于膜的分离具有经济竞争力。该项目将开发一种新的方法，通过作用于膜材料的属性(结合能密度)和形态(自由体积结构)来实现工程选择性。设计具有高结合能密度的材料有望增强膜根据分子的不同溶解度分离分子的能力，并引入提供更均匀和永久自由体积的官能团有望增强基于分子尺寸分离分子的能力。结合高结合能密度和适当的自由体积结构，将产生聚合物膜，显示出以前无法达到的有机分离选择性。这个职业项目将结合实验和计算方法，发现一种通过混合商业和新型聚合物制备的新材料。这些共混聚合物将被明智地选择，以显示出高的内聚能量密度，并具有显示不可折叠的自由体积结构的多孔网络。这些材料的结构将进行系统调整，以最大限度地提高对目标物种的选择性，同时确保优异的长期稳定性。同样重要的是，这个职业项目将促进基于发现的学习，面向高中、本科生、研究生、他们的家庭和普通公众。这一项目的成果将直接在课堂上传播，通过讲习班和高中教育单元提高公众的科学和工程素养，并通过有影响力的会议演讲和科学期刊上的出版物传播。这个职业项目的科学目标是发现、合成和了解用于有机溶剂反渗透和纳滤的下一代聚合物膜。结合能量密度和构型自由体积的LEIT主题将被用于设计这些具有增强长期稳定性的高选择性膜。基本假设是，聚合物膜的溶解选择性随着结合能密度的增加而增加，扩散选择性通过引入赋予不可折叠构型自由体积的iptycene部分而系统地增加。使用实验和理论相结合的方法来验证这些假设，该项目将导致高度选择性和稳定的有机分离用聚合物膜，并将丰富对基于膜的有机分离的结构-性质相关性的基本理解。这一跨学科研究计划将利用材料发现、合成、表征和建模作为一种工具，在不同水平教育不同的学生群体，并提高普通公众的科学和工程素养。研究和教育将通过i)为俄克拉荷马州诺曼地区的初中生和高中生提供的教育模块，ii)美国西南部地区的高级聚合物研讨会，iii)俄克拉荷马大学为化学工程专业的学生提供的新课程，以及iv)为不同的研究生、本科生和初中/高中生提供跨学科培训机会。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。