CAREER: Formation of Stable Polymer Glasses

职业：稳定聚合物玻璃的形成

• 批准号: 1053144
• 负责人: Rodney Priestley
• 金额: $ 50万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1053144&HistoricalAwards=false
• 关键词: CAREER; Formation; Stable; Polymer; Glasses

TECHNICAL SUMMARY: The properties of glasses strongly depend on the path to glass formation. Low energy, ultra-stable organic molecular glasses can be formed by physical vapor deposition. This route to producing ultra-stable glasses is not amenable to polymers. As such, the formation of low energy, ultra-stable polymer glasses have not been realized. The first objective of this CAREER award is to explore Matrix Assisted Pulsed Laser Evaporation (MAPLE) as a route to produce low-energy, ultra-stable polymer films. Processing parameters to be explored include growth rate (both instantaneous and average), substrate temperature, and kinetic energy of the depositing molecule. The stability, morphology, and mechanical properties will be characterized for all films. The second objective of this CAREER is to explore the mechanism of stable glass formation. Here, new experiments are proposed to explore the relationship between stable glass formation and surface mobility. First, the stability of polymer glasses that exhibit different enhanced surface mobility will be compared. Second, the stability of polymer films formed with different surface area/volume ratios will be compared. Third, a unique fluorescence multilayer approach that will allow for the direct measurement of free surface stability and energy-landscape surface will be developed. Fundamental questions this proposal will address include: Do films with greater surface mobility form more stable glasses? Are surface molecules able to explore lower energy states? NON-TECHNICAL SUMMARY: The work addresses fundamental questions concerning low-energy, stable glass formation, and, ultimately, the work may someday provide guidelines for the development of polymer glasses with unmatched thermal and kinetic stability. This proposal will explore one possible application of stable polymer glasses as ultra-barrier membranes. Other potential applications of these materials include 1) displays based on organic light-emitting diode technology, possessing enhanced stability to environmental factors (e.g., humidity, temperature fluctuations), and lower power consumption, 2) organic electronics with greater morphological stability, and 3) coatings and protective skin layers exhibiting greater resistance to contaminants. The new discovery of low energy, stable glasses will be incorporated into a new undergraduate/graduate elective course on the glass transition. The proposed research will be accomplished by a diverse team of high school, undergraduate and graduate students. This CAREER award outlines a unique 4-tier educational and outreach program to increase the number of underrepresented minorities and students from economically disadvantaged backgrounds interested in science, obtaining STEM degrees, and participating in academic research. The outreach program is designed to promote scientific involvement at all levels of a scientific career path.

技术摘要：玻璃的性能很大程度上取决于玻璃形成的路径。 低能量、超稳定的有机分子玻璃可以通过物理气相沉积形成。 这种生产超稳定玻璃的方法不适用于聚合物。 因此，低能量、超稳定聚合物玻璃的形成尚未实现。 该职业奖的第一个目标是探索基质辅助脉冲激光蒸发 (MAPLE) 作为生产低能量、超稳定聚合物薄膜的途径。 要探索的工艺参数包括生长速率（瞬时和平均）、基底温度和沉积分子的动能。 所有薄膜的稳定性、形态和机械性能都将得到表征。 该职业的第二个目标是探索稳定玻璃形成的机制。在这里，提出了新的实验来探索稳定玻璃形成和表面迁移率之间的关系。首先，将比较具有不同增强表面迁移率的聚合物玻璃的稳定性。 其次，将比较不同表面积/体积比形成的聚合物膜的稳定性。 第三，将开发一种独特的荧光多层方法，该方法将允许直接测量自由表面稳定性和能量景观表面。 该提案将解决的基本问题包括：具有更大表面迁移率的薄膜是否会形成更稳定的玻璃？表面分子能够探索较低能态吗？ 非技术摘要：这项工作解决了有关低能、稳定玻璃形成的基本问题，最终，这项工作有一天可能为开发具有无与伦比的热稳定性和动力学稳定性的聚合物玻璃提供指导。 该提案将探索稳定聚合物玻璃作为超阻隔膜的一种可能应用。 这些材料的其他潜在应用包括：1）基于有机发光二极管技术的显示器，对环境因素（例如湿度、温度波动）具有更高的稳定性，并且功耗更低；2）具有更高形态稳定性的有机电子器件；3 ）涂层和保护性表层表现出更强的抗污染物能力。低能稳定玻璃的新发现将被纳入新的本科生/研究生玻璃转变选修课程中。 拟议的研究将由高中生、本科生和研究生组成的多元化团队完成。 该职业奖概述了一个独特的 4 级教育和推广计划，旨在增加对科学、获得 STEM 学位和参与学术研究感兴趣的少数族裔和来自经济弱势背景的学生的数量。 该推广计划旨在促进科学职业道路各个层面的科学参与。