Safety of goods and civilians towards the terrorist risk constitutes a research orientation of public interest, confirmed by the 2013 edition of the “Livre blanc de la Défense et de la Sécurité Nationale”. In particular, the risk of Nuclear or Radiological attack remains one probable and serious risk, following the emergence of nations sufficiently developed and favorable to develop this kind of armament. In this context, it is important to have passive detection of ionizing rays. In our case, we take interest in the detection of neutrons, immutable signature of the presence of materials allowing the preparation of nuclear weapons. In addition to the societal aspect, the economic aspect is crucial because such detectors, containing 3He gas, currently exist, but their lack prevents their deployment on large surfaces. We thus wish to develop polymeric materials allowing the detection of these neutrons at lower costs, as well as a prototype containing these sensors.