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

项目概要 该小型企业技术转让第一阶段项目建议开发和优化 商业上可行的新型聚合物基辐射剂量计，可广泛部署。辐射 本文提出的剂量计是一项具有重要市场的颠覆性技术。虽然很多商业 辐射剂量计测量个人辐射负荷、剂量量化和暴露时间；价值 本文描述的设备的主张是具有同等性能但价格降低 10 倍。 经过优化、商业化和生产，剂量计将允许实时个人 辐射暴露。初始产品将瞄准辐射暴露可能性较高的利基市场，例如 作为核电站工作人员。灵敏度的进一步优化将打开更广阔的市场，例如医疗 应用（即 X 射线技术人员）和放射肿瘤学。最后，为了实现 NIEHS 的总体目标 提供用于环境监测的传感器，所提出的剂量计的成本和性能将允许 广泛部署人员以确定大量人群的个人辐射负荷。 因此，Seacoast Science, Inc.和Timothy Swager教授（麻省理工学院）联合提出了这种剂量计 基于 MIT 开发的基本原理/技术 (Angewandte Chemie, 2010, 122(1), 99-102)。在 最初的工作是，双电极导电剂量计涂有多壁碳纳米管 (MWCNT)/聚合物共混物；暴露于伽马辐射后，测得的电导从 增加互连的纳米电路。尽管结果令人印象深刻，但仍需要进行导电测量 敏感的研究级电子产品。此外，初始聚合物/MWCNT聚合物共混物显示出亚 最佳灵敏度。该项目解决了技术障碍：优化聚合物/MWCNT 敏感性；使用更灵敏的剂量计平台；以及设计/制作适当尺寸的徽章 读出。因此，在该一期项目中，选择了一系列带有侧基的聚烯烃砜用于 最佳聚合物/ MWCNT 相互作用和最大辐射（γ）横截面积将为 麻省理工学院合成。这些聚合物将与不同等级的多壁碳纳米管结合 生产新颖的混合物。这些混合物将被涂在 Seacoast Science 专有的电容式传感器上 将设计和制造平台和适当的配套电子设备。分析性的 然后将使用麻省理工学院的辐射源来确定这些新型剂量计的性能。 基本假设是传感器微观结构和电容式换能器将导致 与这些辐射剂量计中的 Swager 聚合物/CNT 材料结合使用时，灵敏度更高。 由于辐射引起的解聚会增加 CNT-CNT 接触，因此距离超过 可以极化的电荷也急剧增加。这些空间电荷效应是最大的 电容的贡献者，并且可以在比暴露低得多的辐射暴露下轻松测量 需要在电极之间形成渗透导电网络。的分析性能 剂量计将通过暴露于不断增加的伽马辐射剂量来确定，测量的响应， 以及选择用于进一步二期开发的最佳聚合物共混物。

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.