Development of integrated Radiation Dosimeters using Organic Polymer Films

• Project/Area Number: 04558031
• Research Category: Grant-in-Aid for Developmental Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: Nuclear engineering
• Research Institution: National Laboratory for High Energy Physics (KEK)
• Principal Investigator: KONDO Kenjiro Radiation Safety Control Center, KEK ; Prof., 放射線安全管理センター, 教授 (20004434)
• Co-Investigator(Kenkyū-buntansha): MIURA Taichi Radiation Safety Control Center, KEK ; Res.Associate, 放射線安全管理センター, 助手 (80209717) ; NUMAJIRI Masaharu Radiation Safety Control Center, KEK ; Res.Associate, 放射線安全管理センター, 助手 (20189385) ; OKI Yuichi Radiation Safety Control Center, KEK ; Res.Associate, 放射線安全管理センター, 助手 (40204094) ; SUZUKI Takenori Radiation Safety Control Center, KEK ; Assist.Prof., 放射線安全管理センター, 助教授 (40162961)
• Project Period (FY): 1992 – 1993
• Project Status: Completed (Fiscal Year 1993)
• Budget Amount: ¥10,900,000 (Direct Cost: ¥10,900,000); Fiscal Year 1993: ¥4,300,000 (Direct Cost: ¥4,300,000); Fiscal Year 1992: ¥6,600,000 (Direct Cost: ¥6,600,000)
• Keywords: Radiation Dosimetry / Polyaniline / Solid State Detecter / Gamma-ray Irradiation / Conducting Polymer / Radiation-induced Doping / gamma線照射 / ドーピング / 電子線照射 / Y線照射

Research Abstract

In this work, new integrated radiation dosimeters using polymer films were developed and their characteristics were tested by irradiation experiments. As the polymer films, we selected conducting polymers such as polypyrrole and polyaniline. The dosimeters we developed can measure radiation dose as change of electrical conductivity of the film. Its principle is based on radiation-induced doping. The dosimeter consists of a strip of an undoped-polyaniline and a source material of dopant gas. In radiation fields, the polyaniline film is doped with the dopant gas which is formed by radiolysis of the source material, and this radiation-induced doping results in an increase of its conductivity.
Halogenated materials were used as the source material. The polyaniline dosimeters, using polyvinylchloride (PVC), brominated epoxy resin and benzene hexachloride as the source materials, showed drastic increase in conductivity of the polyaniline in proportion to dadiation dose. Especially in the polyaniline-PVC powder system, the conductivity increased linearly with an increase of dose in the wide range of about 10 to 10^5 Gy, and the radiation-induced doping was found to proceed quantitatively in proportion to the dose. This linear relation is one of important characteristics required for an integrated radiation dosimeter. It is considered that the increase in conductivity can be expressed as a function of the dopant content absorbed on the polyaniline film, and the amount of dopant depends of the G-value of the dopant gas liberated from the source material, weight of the source material and integrated radiation dose. The measurable dose range can be controlled by optimizing these factors. This measurement method and our dosimeters are, therefore, very promising for measurement of an integrated radiation dose in wide ranges.

Research Products

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