EAGER: The Verge of Percolation in Nanoparticle Networks

EAGER：纳米粒子网络渗透的边缘

• 批准号: 1254107
• 负责人: Micah Green
• 金额: $ 6.01万
• 依托单位: Texas Tech University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-10-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1254107&HistoricalAwards=false
• 关键词: EAGER; Verge; Percolation; Nanoparticle; Networks

This EArly-concept Grant for Exploratory Research (EAGER) award provides funding to evaluate the feasibility of producing graded nanocomposites with controlled linear nanofiller concentration profiles. Experimental research aims focus on a custom processing technique where dual ramped-flowrate pumps, a static mixer, and rapid curing are used to create nanofiller-loaded polymer composites with a constant gradient in reinforcement. The concentration profile will be measured by light absorbance in samples taken from the composite precursor prior to curing. The conductivity profile will be tested pointwise using a four-point probe after curing. The desired nanofiller is pristine graphene, a nanomaterial prized for its outstanding combination of transport properties. Polymer matrices to be explored include Polydimethylsiloxane and epoxy. Because the graphene sheets are conductive, it is hypothesized that the axial conductivity profile mimics percolation scaling laws such that gradient composites may be used to investigate how percolation threshold and critical scaling exponent are affected by varying dispersion quality, nanofiller geometry, and nanofiller size as a function of sonication. If successful, this project will provide nanoscale insight (into percolating network architecture) and contribute to advanced material functionality (in sensing applications in the aerospace and energy industry). The composites produced by this technique will allow for high-accuracy, high-repeatability comparative studies of nanofiller percolation within polymer matrices. Such composites have immediate application to a range of engineering needs, particularly in next-generation piezoresistive smart materials. Broad scientific communities affected by this exploratory work include those interested in nanomaterial exfoliation and dispersion, composite manufacture, percolation theory, and nanomaterial electrical contacts and networks.

这一早期概念探索性研究(AGER)奖提供资金，以评估生产具有受控线性纳米填料浓度分布的分级纳米复合材料的可行性。实验研究的重点是定制加工技术，其中使用双斜面流量泵、静态混合器和快速固化来创建具有恒定增强梯度的纳米填料加载的聚合物复合材料。浓度分布将通过在固化前从复合前体中获取的样品的光吸收来测量。固化后，将使用四点探头逐点测试电导率分布。理想的纳米膜是原始的石墨烯，这是一种纳米材料，因其出色的传输性能组合而备受推崇。待探索的聚合物基质包括聚二甲基硅氧烷和环氧树脂。由于石墨烯薄片具有导电性，假设轴向电导率分布模拟了渗流标度规律，因此梯度复合材料可以用来研究不同分散质量、纳米填料几何形状和纳米填料尺寸作为超声波的函数如何影响渗流阈值和临界标度指数。如果成功，该项目将提供纳米级的洞察(渗透网络体系结构)，并为先进的材料功能(航空航天和能源行业的传感应用)做出贡献。通过这种技术生产的复合材料将允许对聚合物基质中的纳米填料渗流进行高精度、高重复性的对比研究。这种复合材料立即应用于一系列工程需求，特别是在下一代压阻智能材料中。受这项探索性工作影响的广泛科学界包括对纳米材料剥离和分散、复合材料制造、渗流理论以及纳米材料电接触和网络感兴趣的人。