Structured Fluids from Reduced Symmetry Molecules

减少对称性分子的结构化流体

• 批准号: 0964765
• 负责人: Antal Jakli
• 金额: $ 69万
• 依托单位: Kent State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2014-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0964765&HistoricalAwards=false
• 关键词: Structured; Fluids; Reduced; Symmetry; Molecules

TECHNICAL SUMMARYRecent studies of a team by A. Jákli, J.T. Gleeson and S. Sprunt at Kent State University have clearly demonstrated that fluids built from "bent-core" (or "banana" -shaped) molecules exhibit strikingly different properties from those composed of rod-shape materials; examples include anomalous flow viscosity and giant electro-mechanical coupling the latter being of high technological promise for molecular-scale energy conversion applications. These materials also apparently possess complex structure on the nanometer scale, and exhibit indications of novel states of matter. To develop a complete comprehension of these structures, the Kent State Group will utilize a powerful range of carefully targeted experimental techniques, available in house or through active participation in national user facilities. Specific new classes of reduced-symmetry materials to be investigated include molecules having W, T, X and H-shape, exciting new polymeric fluids and gels based on bent-core molecules, as well as previously uninvestigated low molecular weight bent-core molecules. The specific research objectives and scientific benefits of the proposed research are: (1) specific elucidation of nanoscopic structure in bent-core fluids; (2) investigation into the origins and limits of anomalously large coupling between electric properties and mechanical deformation (3) studies of strongly asymmetric bent-core molecules that form novel three-dimensional structures; (4) investigation of the optical and electro-mechanical properties of main- and side- chain polymers containing bent-core sub-units; and (5) studies of structured fluids under high magnetic fields to search for field-induced symmetry breaking transitions.NON-TECHNICAL SUMMARYStructured fluids are not only of fundamental scientific interest but have also enormous technological importance. Perhaps the most familiar example is liquid crystals, whose applications range from iPod screens to bullet-proof vests. The key factor determining the physical behavior of structured fluids is the symmetry properties of the molecular constituents. The team of A. Jákli, J.T. Gleeson and S. Sprunt at Kent State University will study compounds whose building blocks are not simple rods as in traditional liquid crystals, but either bent-shape, W, T, X and H shaped. A symmetry change in underlying molecule shape can lead to dramatically different and technologically promising behavior of a fluid composed of such molecules. This project offers the promise of significant advances in technology, such as low-cost, wearable (or potentially bio-implantable) electricity generators based on enhanced electro-mechanical coupling and a new generation of fast, low-power reflective color displays. The proposed research will provide critical feedback for synthetic chemists to improve material properties; key collaborators in this effort include Profs. R. Twieg (Department of Chemistry, Kent State University) and R. Verduzco (Department of Chemical Engineering, Rice University). The team's multi-faceted education program will train doctoral students to be effective players in a twenty-first century entrepreneurial environment. The principal investigators also will bring undergraduates, particularly from colleges serving traditionally under-represented groups, into a cutting-edge research environment, with the goal of increasing their participation in the high-tech workforce of tomorrow.Support from the Solid State and Materials Chemistry program is acknowledged.

技术摘要 肯特州立大学 A. Jákli、J.T Gleeson 和 S. Sprunt 团队的最新研究清楚地表明，由“弯核”（或“香蕉”形）分子构成的流体表现出与其他分子截然不同的特性。棒状材料；例子包括反常流动粘度和巨大的机电耦合，后者对于分子尺度的能量转换应用具有很高的技术前景。为了全面理解这些结构，肯特州立集团将利用一系列强大的、精心设计的实验技术，这些技术可以在内部使用，也可以通过国家用户的积极参与来实现。待研究的特定新型减少对称性材料包括具有W、T、X和H形状的分子、基于弯核分子的令人兴奋的新型聚合物流体和凝胶，以及以前未研究的低分子量弯核分子。具体的研究目标。拟议研究的科学益处是：（1）具体阐明弯曲核心流体中的纳米级强结构；（2）研究电特性和机械变形之间异常大耦合的起源和限制（3）非对称弯曲的研究形成新颖三维结构的核心分子；（4）研究含有弯曲核心子单元的主链和侧链聚合物的光学和机电性能；（5）研究高磁场下的结构流体；搜索结构流体不仅具有基础科学意义，而且具有巨大的技术重要性，也许最熟悉的例子是液晶，其应用范围从 iPod 屏幕到防弹背心。决定结构流体物理行为的因素是分子成分的对称性，肯特州立大学的 A. Jákli、J.T. Gleeson 和 S. Sprunt 团队将研究其结构的化合物。块体不是传统液晶中的简单棒，而是弯曲形状、W、T、X 和 H 形。基础分子形状的对称性变化可以导致由此类分子组成的流体具有显着不同且技术上有前景的行为。该项目有望带来重大技术进步，例如基于增强机电耦合的低成本、可穿戴（或可能生物植入）发电机以及新一代快速、低功耗反射式彩色显示器的研究。提供关键反馈改善材料性能的合成化学家；这项工作的主要合作者包括 R. Twieg 教授（肯特州立大学化学系）和 R. Verduzco（莱斯大学化学工程系）。主要研究人员还将把本科生，特别是来自传统上代表性不足群体的大学的本科生，带入前沿的研究环境，目标是提高博士生在二十一世纪创业环境中的作用。他们对未来高科技劳动力的参与。固态和材料化学项目的支持得到了认可。