Extrapolation of Polymer Aging in Waste Storage with the use of High Energy Beam: Toward an Understanding of Mechanisms by the Analysis of Radicals, Gas and Iixiviation Products Formed

摘要

In the framework of nuclear waste storage, there is a growing interest in the prediction of long-term behaviour of organic materials subjected to high energy radiation. Hence, organic waste (especially polymers present for example in electric cables) stored in presence of radionuclides will be produce gas and low molecular organic molecules. Gas (hydrogen, methane, chloridric acid,..) can have an impact on the integrity (explosion, corrosion) of the container and low molecular organics can be potential complexing agent of radionuclides and have an impact in terms of potential migration within the geosphere. In order to predict such behaviour and to be able to quantify it, it is mandatory to be able to extrapolate at long term (> 100 years) the behaviour of such polymers. For that purpose, a study using a specific polymer (polyurethane) of interest irradiated at low doses and at high doses for accelerating time has been performed since the two main problems that are important are, first the modelling of the oxidation dose rate-effect and, secondly, the influence of dose on the oxidation mechanism.