Molecular design and fundamental understanding of Janus Mixed Matrix Membranes with precisely controlled morphology and transport properties

从气体混合物中分离二氧化碳是减少排放和产生优质甲烷或氢燃料的重要方面。然而，目前的膜材料在选择性和渗透性之间进行权衡，这意味着实现更纯产品的分离需要更多的时间。在这个项目中，研究人员的目标是使用嵌入聚合物膜中的Janus纳米颗粒来提高分离的质量和速度。Janus纳米粒子有两个面，参考罗马神话中的人物。在这种情况下，一面覆盖着银，另一面包含一种称为Jeffamine的聚合物的尾部。银和Jeffamine组分均促进CO2通过膜的运输。该项目有可能促进美国经济和生活质量的提高，因为这将有助于减少美国对传统分离技术的依赖，减轻能源费用，并限制大气中的有害排放。研究人员还计划指导一个多元化的学生研究小组，并通过高中生和公共活动的学习模块展示他们的研究结果。该提案旨在发现关于Janus纳米颗粒的银和聚醚（Jeffamine）组分如何单独和协同地贡献于聚合物膜时的传输特性的基本结构-性质相关性。研究人员假设Janus颗粒的各向异性特性将导致膜传输性能的改善，例如高渗透性，高选择性和更少的缺陷。为了验证这一假设，研究人员将合成两个系列的膜，一个系列含有越来越多的具有固定聚醚尾部长度的Janus纳米颗粒，第二个系列含有固定数量的具有不同长度聚醚尾部长度的Janus纳米颗粒。纳米颗粒的化学结构、粒度和银含量将在将它们添加到聚合物膜之前进行测量。膜表征将包括热、自由体积、重量和结构表征，例如纳米颗粒的分散、链堆积和域间距。拟议活动的结果将是对Janus纳米颗粒特性（如聚醚尾部的醚基数量）如何用于改善CO2选择性和渗透性的基本理解。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Separating carbon dioxide from a mixture of gases is an important aspect of reducing emissions and generating quality methane or hydrogen fuel. However, current membrane materials suffer a trade-off between selectivity and permeability, meaning separations that achieve purer products require more time. In this project, the investigators aim to improve both the quality and speed of the separation using Janus nanoparticles embedded in a polymer membrane. Janus nanoparticles have two faces, in reference to the character in Roman mythology. In this case, one face is covered with silver and the other contains tails of a polymer called Jeffamine. Both the silver and the Jeffamine components facilitate CO2 transport through the membrane. This project has the potential to advance the US economy and quality of life, as is will contribute to reducing the nation's dependency of traditional separation technologies, lightening energy bills, and limiting harmful emissions in the atmosphere. The investigators also plan to mentor a diverse group of student researchers and present their results through learning modules for high school students and public events.This proposal aims to discover fundamental structure-property correlations regarding how silver and polyether (Jeffamine) components of a Janus nanoparticle contribute, individually and synergistically, to transport properties when incorporated into a polymer membrane. The investigators hypothesize that the anisotropic character of the Janus particle will lead to improved membrane transport properties such as high permeability, high selectivity, and fewer defects. To test this hypothesis, the investigators will synthesize two series of membranes, one containing an increasing amount of Janus nanoparticles with a fixed polyether tail length, and second with a fixed amount of Janus nanoparticles exhibiting different lengths polyether tail lengths. The chemical structure, particle size and silver content of the nanoparticles will be measured before adding them to the polymer membrane. Membrane characterization will include, thermal, free volume, gravimetric and structural characterizations such as the dispersion of nanoparticles, chain-packing, and domain spacing. The outcome of the proposed activities will be fundamental understanding of how Janus nanoparticle characteristics, such as the number of ether groups in the polyether tail, can be used to improve both CO2 selectivity and permeability.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.