Development of 300 °C heat resistant boron-loaded resin for neutron shielding

A new neutron shielding material resistant to temperatures up to 300 degrees C is developed, consisting of a phenol-based resin with 6 wt% boron. The resin will be applied around the vacuum vessel of the DD plasma device to suppress the streaming neutrons and to reduce the nuclear heating of the superconducting coils. The neutron shielding performance of the newly developed resin.. examined by the Cf-252 neutron source, is almost the same as that of polyethylene, which is not effective above 100 degrees C. The new resin maintains its mechanical strength in the high temperature region. The outgas of CO, NH3 and H2O from the resin have been measured, however, the neutron shielding performance of the resin after 200 degrees C baking was almost the same as that before baking. Thirteen kinds of organic gases have been observed at similar to 300 degrees C. (c) 2007 Elsevier B.V. All rights reserved.