Advanced Polymer-Based Micro-sensor for Radiation Detection and Measurement

项目摘要 这个小企业技术转让第一阶段项目提出了一个发展和优化， 商业上可行的新型聚合物基辐射剂量计，用于广泛部署。辐射 在此提出的剂量计是具有重要市场的破坏性技术。虽然许多商业 辐射剂量计测量个人辐射负荷、剂量量化和照射时间; 这里描述的设备的建议是价格降低10倍的同等性能。 在优化、商业化和生产后，剂量计将允许实时个人测量。 辐射暴露初期产品将瞄准辐射暴露概率较高的利基市场， 核电站工作人员。灵敏度的进一步优化将打开更广阔的市场， 应用程序（i. e. X射线技师）和放射肿瘤学。最后，为了服务于NIEHS的总体目标， 提供用于环境监测的传感器，建议的剂量计的成本和性能将允许 广泛的人员部署，以确定大量人口的个人辐射负荷。 因此，海岸科学公司。和Timothy Swager教授（麻省理工学院）共同提出了这种剂量计 基于MIT开发的基本原理/技术（Angewandte Chemie，2010，122（1），99-102）。在 在最初的工作中，双电极导电剂量计涂有多壁碳纳米管 （MWCNT）/聚合物共混物;在暴露于γ辐射时，测量的电导从2.5%增加到2.5%。 增加互连纳米电路。尽管结果令人印象深刻， 敏感的研究级电子设备此外，初始聚合物/MWCNT聚合物共混物显示出亚微米级。 最佳灵敏度本项目解决了以下技术难题：优化聚合物/MWCNT 灵敏度;使用更灵敏的剂量计平台;以及设计/制作适当尺寸的标记 读数。因此，在该I期项目期间，选择了一系列具有侧基的聚烯烃砜， 最佳聚合物/ MWCNT相互作用和最大辐射（γ）横截面积将是 在MIT合成的。这些聚合物将与不同等级的多壁碳纳米管相结合 来生产新的共混物。这些混合物将被涂在Seacoast Science的专有电容传感器上 将设计和制造平台和适当的伴随电子设备。分析 这些新的剂量计的性能，然后将确定使用辐射源在麻省理工学院。 基本假设是传感器微结构和电容式换能器将导致 当与这些辐射剂量计中的Swager聚合物/CNT材料组合时，灵敏度增强。 因为辐射诱导的解聚引起增加的CNT-CNT接触，所以在辐射诱导的解聚期间的距离增加。 可被极化的电荷也显著增加。这些空间电荷效应是 电容的贡献者，并且将在比暴露低得多的辐射暴露下容易地测量。 需要在电极之间形成导电网络。的分析性能 剂量计将通过暴露于增加剂量的伽马辐射，测量的响应， 并选择最佳聚合物共混物用于进一步的第二阶段开发。

Project Summary This Small Business Technology Transfer Phase I project proposes the development and optimization of a commercially viable novel polymer based radiation dosimeter for wide-spread deployment. The radiation dosimeter proposed herein is a disruptive technology with a significant market. Although many commercial radiation dosimeters measure individual radiation load, dose quantification and exposure timing; the value proposition of the device described herein is the equivalent performance with a 10-fold reduction in price. Upon optimization, commercialization, and production the dosimeter will allow the real-time individual radiation exposure. Initial products will target niche markets with higher radiation exposure probability such as nuclear power plant personnel. Further optimization in sensitivity will open broader markets such medical applications (i. e. x-ray technician) and in radiation oncology. Finally, in service to the overall goal of NIEHS to provide sensors for environmental monitoring, the cost and performance of the proposed dosimeter will allow widespread personnel deployment to determine the individual radiation load for a large population. Hence, Seacoast Science, Inc. and Professor Timothy Swager (MIT) jointly propose this dosimeter based on underlying principles/technology developed at MIT (Angewandte Chemie, 2010, 122(1), 99-102). In that initial work, a two-electrode conductive dosimeter was coated with a multi-walled carbon nanotube (MWCNT)/polymer blend; upon exposure to gamma radiation, the measured conductance increased from increased interconnected nanocircuitry. Despite impressive results, the conductive measurement required sensitive research-grade electronics. Furthermore, the initial polymer/MWCNT polymer blends displayed sub- optimum sensitivity. Technical hurdles are addressed in this project: optimizing the polymer/MWCNT sensitivity; use of a more sensitive dosimeter platform; and design/fabrication of an appropriate badge-size readout. Accordingly, during this Phase I project, a series of polyolefin sulfones with side groups selected for optimal polymer/ MWCNT interaction and maximum radiation (gamma) cross sectional area will be synthesized at MIT. These polymers will be combined with different grades of multi-walled carbon nanotubes to produce novel blends. The blends will be coated onto Seacoast Science’s proprietary capacitive sensor platform and appropriate accompanying electronics will be designed and fabricated. The analytical performance of these novel dosimeters will then be determined using the radiation source at MIT. The underlying hypothesis is that the sensor microstructure and the capacitive transducer will result in enhanced sensitivity when combined with the Swager polymer/CNT materials in these radiation dosimeters. Because the radiation-induced depolymerization gives rise to increased CNT-CNT contacts, the distance over which charge can be polarized also dramatically increases. These space charge effects are the largest contributor to a capacitance and will be easily measured at much lower radiation exposures than exposures required to form a percolating conductive network between electrodes. The analytical performance of the dosimeters will be determined by exposure to increasing doses of gamma radiation, the response measured, and the optimal polymer blends selected for further Phase II development.