Polymer Ferroelectricity Confined in Nanospaces

技术摘要：这个提案？我们的目标是从纳米约束的角度来理解众所周知的弛豫铁电现象，并利用这些知识为其未来的应用提供指导。与纳米约束铁电陶瓷粒子不同，约束铁电聚合物可能不会表现出所谓的量子约束效应。相反，当约束尺寸从微尺度到纳米尺度逐渐减小，约束几何结构从一维到二维，最后到三维，它们的长链性质和构象灵活性导致了丰富而竞争的铁电多态性。特别是在正常的铁电材料中，偶极子之间的远距离协同相互作用将被破坏或减弱。本项目将采用化学约束和物理约束两种方法。如果成功，本研究将有助于推进基础聚合物科学和铁电聚合物领域的教育；1)纳米约束聚合物铁电是一个新颖的概念，在聚合物领域的研究很少。2)本研究将为铁电聚合物带来新的性能和应用。非技术总结：这个项目的潜在影响有三个方面。首先，受限聚合物铁电将对电能存储应用产生更广泛的影响，例如高能量密度电容器。第二，通过该项目，各级学生，包括本科生、研究生和博士后，将为新兴的能源相关专业职业生涯提供良好的培训。为了实现这一目标，PI将招募本科生和REU学生，特别是代表性不足的学生，进入他的研究实验室。为了让他们接触到铁电聚合物和晶体聚合物的纳米科学，研究生课程“聚合物结构和形态学”将教授本研究成果的新内容。此外，PI还将通过夏季研究项目，与当地高中科学教师建立合作关系，重点关注K-12教育。感兴趣的高中生也将被招募，以激发和加强他们对科学和工程的一般兴趣。最后，研究成果将通过与国家实验室和工业的合作，以及通过在高质量的同行评议期刊上的出版物和在国家和国际会议上的报告广泛传播。

TECHNICAL SUMMARY:This proposal?s objective is to understand the well-known relaxor ferroelectric phenomenon from a viewpoint of nanoconfinement, and use this knowledge to provide guidance for its future applications. Different from nanoconfined ferroelectric ceramic particles, confined ferroelectric polymers may not exhibit the so-called quantum confinement effect. Instead, their long chain nature and conformational flexibility results in rich and competing ferroelectric polymorphism, when the confinement size gradually decreases from micro- to nano-scales and confinement geometry changes from one-dimensional to two-dimensional, and finally to three-dimensional. In particular, the long-range cooperative interactions among dipoles will be broken or weakened in otherwise normal ferroelectric materials. Both chemical and physical confinement methods will be employed in this project. If successful, this proposed research will contribute to the advancement of fundamental polymer science and education in the field of ferroelectric polymers; 1) Nanoconfined polymer ferroelectricity is a novel concept which has seldom been studied in the polymer field before. 2) This research will lead to new properties and applications for ferroelectric polymers.NON-TECHNICAL SUMMARY:Potential impacts of this project are three folds. First, confined polymer ferroelectricity will have a broader impact on electrical energy storage applications, such as high energy density capacitors. Second, through this project, students at all levels, including the undergraduates, graduates, and postdocs, will be well trained for emerging energy-related professional careers. To reach this goal, the PI will recruit undergraduate and REU students, especially underrepresented students, into his research lab. To expose them to the nanoscience of ferroelectric and crystalline polymers, a graduate course, Polymer Structure and Morphology, will be taught with new contents of results from this proposed work. In addition, the PI will also focus on K-12 education by establishing collaborations with local high school science teachers via summer research projects. Interested high school students will also be recruited to stimulate and strengthen their general interest in science and engineering. Finally, research results will be broadly disseminated by collaborations with national laboratories and industries, as well as by publications in quality peer-reviewed journals and presentations at national and international meetings.