LAUSR

Abstract Tritium is radioactive hydrogen isotope which can be easily absorbed by organisms. The release of tritium is harmful to human health and environment. For monitor tritium directly, the development of new scintillator with low excitation energy, high scintillation efficiency and enhanced oxidative resistance, is desired. Polysilane has unique fluorescence characteristics for the σ conjugate structure which allow the excited electrons delocalizing in the whole Si-Si main chain. Polysilane modified by functional side groups would be used as novel tritium-releasing scintillation if it had enough oxidative resistance. In this paper, preliminary study about modified polymethylsilane (PMS) is carried out on the relationship between oxidative resistance and fluorescence properties. The mechanism of oxidation which causes the fluorescence degradation is also discussed. Polymethylsilane grafting aniline groups (PA-PMS) preforms the most prominent fluorescence for the smaller electronegativity of N, but it shows a poor oxidative stability in the air. Its fluorescence properties decline significantly after being placed for a period of time, which is related to the oxidation of the amino group. By contrast, O bridging σ-n-π structure could acceptably provide both fluorescence properties and oxidative resistance at the same time, which are the pressing needs for the scintillator material in tritium monitor.