硅橡胶及其纳米复合材料的长期低剂量率辐射效应研究

Silicone rubbers and their nanocomposites with excellent performance have an important purpose in nuclear power and space area. But due to the existence of intense radiation field, the performance of silicone rubbers and their nanocomposites will inevitably change with the radiation effect of high energy, it is extremely necessary to carry out the related research. In this project, gamma ray long-term irradiation of silicone rubbers and their nanocomposites at low dose rate (0.1-2.0 Gy/min) will be investigated under the condition of different temperature, atmosphere and pressure etc. The change of their performance and radiolytic mechanism after irradiation will be illuminated by using solid nuclear magnetic resonance and electron paramagnetic resonance methods, etc. Further through comparing with gamma ray short-term irradiation at high dose rate (30 Gy/min - 300 Gy/min) irradiation, proton beam irradiation and thermo-oxidative ageing, we will study the effects of dose rate and different radiation source on the structures and properties of silicone rubbers and their nanocomposites, and then establish the model on radiation chemical yield of main radiolytic products based on dose rate changes, explore research method on long-term low dose rate radiation effect and stability evaluation scheme of silicone rubbers and their nanocomposites. This project will provide theoretical and experimental support for long-term stable application of silicone rubbers and their nanocomposites in nuclear radiation field and space radiation environment.

硅橡胶及其纳米复合材料因具有优异的性能在核电及航天等领域有着重要的用途。但因强辐射场的存在，硅橡胶及其纳米复合材料在高能射线作用下其性能将不可避免地发生变化，因而非常有必要开展相关的研究。本项目拟系统研究硅橡胶及其纳米复合材料在不同温度、气氛及加压等条件下的伽玛射线长期低剂量率 (0.1 – 2.0 Gy/min) 辐射效应，采用固体核磁、电子顺磁共振等手段解析辐照后硅橡胶及其纳米复合材料结构性能的变化及辐解机理。进一步通过与伽玛射线高剂量率（30 Gy/min - 300 Gy/min）辐照、质子束辐照及热老化对比，研究剂量率、不同辐射对硅橡胶及其纳米复合材料结构性能的影响，构建主要辐解产物的辐射化学产额基于剂量率变化的模型，探索硅橡胶及其纳米复合材料长期低剂量率辐射效应的研究方法及辐射稳定性的评价方案，为硅橡胶及其纳米复合材料在核辐射场及太空辐射环境中的长期稳定应用提供理论及实验支持。

硅橡胶及其纳米复合材料因具有优异的性能在核电及航天等领域有着重要的用途。但由于强辐射场的存在，硅橡胶及其纳米复合材料在高能射线作用下其性能将不可避免地发生变化，因而非常有必要开展相关的研究。本项目系统开展了硅橡胶及硅橡胶泡沫材料在不同温度、气氛等条件下的长期伽玛射线辐射效应研究，发现硅橡胶及硅橡胶泡沫材料在伽玛射线辐照下发生了以交联为主的反应，且存在明显的剂量率效应。成功制备了硅橡胶/碳纳米管、硅橡胶/GO、硅橡胶/POSS、硅橡胶/MXenes纳米复合材料，发现通过在硅橡胶中添加碳纳米管等纳米材料可赋予其新的功能，并提高了硅橡胶的耐辐射性能。