NER: Polymer Nanowires Synthesized on a Flat Surface Via a Surfactant Template

NER：通过表面活性剂模板在平坦表面上合成的聚合物纳米线

• 批准号: 0210485
• 负责人: Brian Grady
• 金额: $ 10万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0210485&HistoricalAwards=false
• 关键词: NER; Polymer; Nanowires; Synthesized; Flat

Nanoscale materials offer many potential technological applications due to the unusual properties inherent in these materials compared to their traditional macroscale analogues. Conducting polymers are prime targets for nanoscale synthesis as their conductivity is greatly enhanced by highly oriented morphologies. In this proposal, The PI's show for the first time that oriented polyaniline (PANI) nanowires, with almost uniform radii, have been oxidatively synthesized on highly ordered pyrolytic graphite (HOPG) and on mica using anadsorbed surfactant template. They have also synthesized similar structures, but not as ordered, using polypyrrole. The dimensions of the synthesized structure vary depending on the substrate. If a way can be determined to produce conducting nanowires with almost uniform radii so that their center-to-center distances are regular and controllable, then this would have substantial impact in many areas, particularly in the microelectronics industry.The important technological discovery that has allowed them to make these advances is the fact that adsorbed monolayers of surfactant can form very unique structures at the solid-liquid interface. The type of structures range from cylinders, spheres and flat bilayers on hydrophilic surfaces, to half cylinders, half spheres and monolayers on hydrophobic surfaces. Using the results of work done by others, they were able to choose a specific surfactant structure as a patterning template. Their experiments have been successful, in the specific case of adsorbed half-cylinders the resulting film also has what appears to be a half-cylinder morphology for certain polymers and surfaces. The dimensions of the fillers have been measured to be between 50 and 100 nm in diameter, and as long as 150 microns.This exciting new discovery and the work described in this grant have all been completed over the last 4 months. Although AFM micrographs clearly support their claims, their understanding of some critical issues is not complete. For example, the structures vary significantly in dimension (height and width) depending on the substrate and monomer that is used. The wires coalesce; one of the most important issues is to understand why these wires coalesce, and determine, if possible, a way to reduce or arrest coalescence. They know almost nothing about the properties of these nanowires, including their conductivity, and clearly the properties of the wires is extremely important. This grant will enable them to explore all of these issues and help them to achieve the ultimate goal, the synthesis of fully dispersed nanowires oriented in one direction over very large length scales.

纳米材料提供了许多潜在的技术应用，由于这些材料与传统的宏观类似物相比具有不寻常的特性。导电聚合物是纳米级合成的主要目标，因为它们的导电性通过高度取向的形态大大增强。在这一提议中，PI的首次表明，取向聚苯胺（PANI）纳米线，几乎均匀的半径，已氧化合成高度有序的热解石墨（HOPG）和云母使用吸附的表面活性剂模板。他们还合成了类似的结构，但不是有序的，使用聚吡咯。合成结构的尺寸根据基底而变化。如果能够确定一种方法来生产具有几乎均匀半径的导电纳米线，使其中心到中心的距离是规则的和可控的，那么这将在许多领域产生重大影响，特别是在微电子工业中。使他们取得这些进展的重要技术发现是表面活性剂的吸附单层可以在固液界面形成非常独特的结构。结构的类型范围从亲水表面上的圆柱体、球体和平坦双层到疏水表面上的半圆柱体、半球体和单层。利用其他人的工作结果，他们能够选择特定的表面活性剂结构作为图案化模板。他们的实验是成功的，在吸附的半圆柱体的特定情况下，所得的膜对于某些聚合物和表面也具有似乎是半圆柱体的形态。填料的尺寸已被测量为直径在50和100纳米之间，长达150微米。这一令人兴奋的新发现和这项授权中描述的工作都是在过去4个月内完成的。虽然AFM显微照片清楚地支持他们的说法，但他们对一些关键问题的理解并不完整。例如，取决于所使用的基底和单体，结构在尺寸（高度和宽度）上显著变化。金属丝聚结;最重要的问题之一是理解为什么这些线聚结，并且如果可能的话，确定减少或阻止聚结的方法。他们对这些纳米线的性质几乎一无所知，包括它们的导电性，显然这些线的性质是极其重要的。这笔赠款将使他们能够探索所有这些问题，并帮助他们实现最终目标，即在非常大的长度尺度上合成完全分散的纳米线。