Controlling Nanocomposite Properties by Nanoparticle Assembly

通过纳米颗粒组装控制纳米复合材料性能

• 批准号: 1408323
• 负责人: Sanat Kumar
• 金额: $ 46万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1408323&HistoricalAwards=false
• 关键词: Controlling; Nanocomposite; Properties; Nanoparticle; Assembly

NON-TECHNICAL SUMMARY:There has been continuing interest in polymer nanocomposites, which are mixtures of polymeric materials and nanometer-sized inorganic particles, primarily because they offer the promise of significantly improved physical properties relative to the corresponding pure polymer. While there have been many studies on these topics to date, very few have gone from the scientific details relevant to controlling the nanoparticle (NP) dispersions to optimizing the practically relevant thermal and mechanical properties that emerge. Each of the three prongs of this research project focuses on establishing this connection in a way that has a direct impact on applications. (i) The proposed research on pressure effects will delineate the role of processing in homogenizing polymer/NP mixtures and the consequences of this changing dispersion state on properties. (ii) In a second thread, this research will study the role of NP shape on optimizing thermal and mechanical properties. (iii) Finally, the practical consequences of the proposed research will be explored by replacing chemically attached polymer molecules on the NPs by the physically attached ones. Are these strategies equivalent, and, if not, in what tangible ways are they different?These research efforts will be coupled to a suite of education and outreach activities. Driven by the group's recent activities involving recruiting high school and undergraduate students for summer research, the proposal is to continue to recruit students from historically minority schools (such as Florida A&M), as well as undergraduate and high school students (and teachers) from the greater New York City environment. The PI's group has previously worked with several women and minority high-school students who have subsequently gone on to study science and engineering in college, and will continue this pipeline approach toward science and engineering careers.TECHNICAL SUMMARY:There has been continuing interest in polymer nanocomposites, primarily because these hybrids offer the promise of significant property improvements relative to the pure polymer. While there have been many studies on this topic to date, very few of them have gone all the way from controlling the nanoparticle (NP) dispersion state to optimizing the thermomechanical properties that emerge. The overall approach proposed, which combines experiments and theory, focuses precisely on bridging this gap by (a) studying the fundamentals of the assembly process and its consequences on properties, and (b) porting the evolving understanding to make it more amenable to applications. The proposed research has the following three prongs: (i) Critically studying the role of pressure in homogenizing polymer/NP mixtures. Can high pressure be used to control NP dispersion and what are its effects on properties? (ii) Similarly, the research will explore the role of NP shape as a route to further optimizing thermomechanical properties. (iii) Finally, the practical consequences of the proposed research will be studied by replacing chemically-grafted chains on the NPs by the physical adsorption of chains. Is this idea feasible and what are its advantages and disadvantages in terms of property improvements?These research activities are coupled to extensive education and outreach activities. Driven by the group's recent activities involving high school and undergraduate students for summer research, and with the group's well-developed interactions with Florida A&M University (an HBCU), the proposal is to continue to recruit underrepresented students (both women and minorities) at the high school, undergraduate and graduate levels to be part of the group's research efforts. The PI is also working with the Chemical Engineering department at the City College of New York to bring together academics in the Greater New York area (faculty and students), local industry and national laboratories in an annual chemical engineering symposium. The goal is, not only to place graduating students into local industry, but also to attract industrial participants into higher degree and/or refresher programs at Columbia.

非技术摘要：对聚合物纳米复合材料的持续兴趣，它们是聚合物材料和纳米尺寸的无机颗粒的混合物，主要是因为它们提供了相对于相应纯聚合物的显着改善物理性能的希望。尽管迄今为止对这些主题进行了许多研究，但很少有从控制纳米颗粒（NP）分散的科学细节到优化出现的实际相关的热和机械性能。该研究项目的三个方面中的每一个都侧重于建立这种联系，以直接影响应用程序。 （i）拟议的关于压力效应的研究将描述加工在均质聚合物/NP混合物中的作用，以及这种不断变化的分散状态对性质的后果。 （ii）在第二个线程中，这项研究将研究NP形状在优化热和机械性能中的作用。 （iii）最后，将通过通过物理附着的化学分子代替NP上的化学连接的聚合物分子来探索所提出的研究的实际后果。这些策略是否等效，如果没有，它们以哪些切实的方式与众不同？这些研究工作将与一套教育和外展活动相结合。在该小组最近的活动涉及招募高中和本科生进行夏季研究的情况下，该提议将继续招募来自历史悠久的少数民族学校（例如佛罗里达州A＆M）的学生，以及大纽约市环境的本科生和高中生（和高中生（和教师）。 PI的小组以前曾与几位女性和少数族裔高中生合作，这些学生随后继续学习大学的科学和工程学，并将继续采用这种用于科学和工程职业的管道方法。技术摘要：主要是因为这些混合体提供了相对于纯Polymerser的聚合物纳米复合物的持续兴趣，主要是因为这些混合体提供了显着的物业改善。尽管迄今为止对此主题进行了许多研究，但其中很少有从控制纳米颗粒（NP）分散状态到优化出现的热力学特性的一路走来。结合实验和理论的总体方法是通过（a）研究组装过程的基本原理及其对性质的后果，以及（b）移植不断发展的理解以使其更适合应用程序。拟议的研究具有以下三个方面：（i）批判性地研究压力在均质聚合物/NP混合物中的作用。可以使用高压来控制NP分散体，其对特性有什么影响？ （ii）同样，该研究将探讨NP形状作为进一步优化热机械特性的途径的作用。 （iii）最后，将通过通过链的物理吸附来代替NP上的化学链链来研究拟议研究的实际后果。这个想法是可行的吗？在财产改善方面，其优势和缺点是什么？这些研究活动与广泛的教育和外展活动相结合。在该小组最近涉及高中和本科生进行夏季研究的活动中，以及该小组与佛罗里达A＆M大学（HBCU）的互动良好的互动，该提议将继续在高中学生（妇女和少数群体）中继续招募小学生，不足的学生和研究生级别的一部分。 PI还与纽约市城市学院的化学工程系合作，将纽约地区（教职员工和学生），地方工业和国家实验室的学者组合在一起。目的是，不仅将毕业生的学生纳入本地行业，而且还将工业参与者吸引到哥伦比亚的更高学位和/或复习计划。