Finding Order in Chaos: Vibrational Spectroscopy Study of Oriented Soft Materials

在混沌中寻找秩序：定向软材料的振动光谱研究

• 批准号: RGPIN-2020-05098
• 负责人: Pellerin, Christian
• 金额: $ 3.5万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=748703
• 关键词: Finding; Order; Chaos; Vibrational; Spectroscopy

The properties and performance of soft materials depend on their chemical nature and on their molecular structure: how the molecules are arranged within the material. The orientation of molecules is a critical aspect of materials structure. It plays a large role in high-performance fibers, in films that extend food shelf-life, in televisions and flat screens, etc. Our group specializes in the study of orientation: we develop new techniques of vibrational spectroscopy to better analyze orientation and we create orientation in otherwise chaotic (amorphous and disordered) materials to improve their properties. This research targets three specific objectives in line with our existing program on oriented materials. First, we want to gain a fundamental understanding of "photomobility" in materials containing azobenzene (azo) chemical units. In this intriguing phenomenon, irradiation with polarized light induces a molecular-scale isomerization of the azo that leads to an intermediate scale orientation and finally to large-scale motion. We will apply vibrational spectroscopy and other tools to better understand the highly debated mechanism of photomobility. The second objective is to optimize the molecular design of azomaterials for efficient "photomechanical" applications where light energy is converted into motion or work. We will use, among others, a time-resolved spectroscopy method (developed in our lab) to study the role of the glass transition temperature, the bulkiness of the azo, its isomerization efficiency, etc., on light-induced orientation and motion. Finally, we will develop new methods of vibrational spectroscopy that will sidestep limitations of the existing techniques to measure orientation. We will apply them to nanofibers prepared by electrospinning, a technique with highly promising application prospects but whose widespread use is limited by our poor control of the properties of nanofibers. Our research is innovative and, thanks to our specific expertise and state-of-the-art infrastructure, it could not be conducted elsewhere in the world. It will have significant impact at three levels. First, it will contribute to the training of 20 students in the thriving field of materials science. Our previous students are now active in research and industry in Canada and abroad. Second, we will cast new light on the role of orientation in amorphous materials and on the exciting phenomena of photomobility and mass transport in azomaterials. This knowledge will help optimize the performance of partially ordered soft materials. Our new spectroscopy techniques should also be adopted by other researchers worldwide. Finally, we will have an immediate practical impact thanks to our ongoing collaborations with industrial and military partners who seek our expertise in orientation and spectroscopy to improve their real-world applications.

软材料的特性和性能取决于它们的化学性质和分子结构：分子如何在材料中排列。分子的方向是材料结构的关键方面。它在高性能纤维，在延伸食物货架寿命，电视和平面屏幕等的电影中起着重要作用。我们的小组专门研究方向研究：我们开发了振动光谱的新技术，以更好地分析方向，我们在其他混乱（异形和无序）材料中创造了方向，以改善其财产。这项研究针对我们现有的定向材料计划的三个特定目标。首先，我们希望在含有偶氮苯（Azo）化学单元的材料中获得对“光性性”的基本理解。在这种有趣的现象中，用偏振光照射会引起偶氮的分子尺度异构化，从而导致中间尺度的方向，最后进行大规模运动。我们将应用振动光谱和其他工具，以更好地理解高度争论的发光性机制。第二个目的是优化AZOMATERIALS的分子设计，以进行有效的“光学”应用，其中光能转化为运动或工作。我们将使用一种时间分辨的光谱法（在我们的实验室中开发）来研究玻璃过渡温度的作用，偶氮的体积，其异构化效率等在光引起的方向和运动中。最后，我们将开发新的振动光谱方法，以避开现有技术的限制以测量方向。我们将将它们应用于通过静电纺丝制备的纳米纤维，这是一种具有高度希望的应用前景的技术，但其宽度的使用受到我们对纳米纤维性能的不良控制的限制。我们的研究具有创新性，感谢我们的具体专业知识和最先进的基础设施，它不能在世界其他地方进行。这将在三个级别上产生重大影响。首先，它将有助于培训20名材料科学领域的学生。我们以前的学生现在积极从事加拿大和国外的研究和行业。其次，我们将向非晶材料以及非洲材料的令人兴奋的现象和质量转运现象投入新的启示。这些知识将有助于优化部分有序的软材料的性能。我们的新光谱技术也应由全球其他研究人员采用。最后，我们将立即产生实际影响，还要与我们与工业和军事合作伙伴进行的持续合作，他们寻求我们在定向和光谱方面的专业知识，以改善其现实世界的应用。