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

项目摘要 该小型企业技术转移第一阶段项目建议开发和优化 商业上可行的新型聚合物辐射剂量计，用于广泛部署。辐射 本文提出的剂量计是一项具有很大市场的颠覆性技术。尽管许多商业广告 辐射剂量计测量个人辐射负荷、剂量量化和照射时间；值 这里描述的设备的主张是在价格降低10倍的情况下具有同等的性能。 在优化、商业化和生产后，剂量计将允许实时个人 辐射暴露。首批产品将瞄准辐射暴露概率较高的利基市场，如 作为核电站的工作人员。敏感度的进一步优化将打开更广阔的市场，如医疗 在放射肿瘤学中的应用(即X射线技师)。最后，为了服务于NIEHS的总体目标， 为环境监测提供传感器，拟议的剂量计的成本和性能将允许 广泛部署人员，以确定大量人口的个人辐射负荷。 因此，海岸科学公司和麻省理工学院的蒂莫西·斯威格教授共同提出了这种剂量计 基于麻省理工学院开发的基本原则/技术(Angewandte Chemie，2010,122(1)，99-102)。在……里面 最初的工作是用多壁碳纳米管涂覆双电极电导剂量计 (MWCNT)/聚合物共混物；暴露于伽马辐射后，测量的电导从 增加了互连的纳米电路。尽管结果令人印象深刻，但导电测量需要 灵敏的研究级电子产品。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 敏感度；使用更灵敏的剂量计平台；设计/制造合适的徽章尺寸 读数。因此，在这一阶段项目中，一系列侧基被选择用于 最佳聚合物/多壁碳纳米管相互作用和最大辐射(伽马)横截面积 在麻省理工学院合成的。这些聚合物将与不同等级的多壁碳纳米管结合 来生产新的混合物。这种混合物将被涂在海岸科学公司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。 潜在的假设是传感器的微观结构和电容式换能器将导致 在这些辐射剂量计中，当与Swager聚合物/碳纳米管材料结合使用时，可提高灵敏度。 由于辐射诱导的解聚导致碳纳米管-碳纳米管接触增加，因此 可以极化的电荷也急剧增加。这些空间电荷效应是最大的 对电容的贡献，在比曝光量低得多的辐射曝光量下很容易测量 在电极之间形成渗流导电网络所需的。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、测量的响应、 并选择用于第二阶段进一步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.