Suitability of aromatic polyurethanes for use in nuclear applications

Plastic bags are used to facilitate the storage and transport of nuclear materials. In case the storage container becomes damaged, these bags act as a protection barrier against possible contamination. Polyvinyl chloride (PVC) is a polymer commonly used in such applications, but unfortunately, it contributes to the corrosion of the metal container due to HCl evolution. Thus, this work evaluated aging effects on chemical and thermo-mechanical properties of aromatic polyurethanes with the intent to find a replacement for PVC. Aromatic poly(ether)urethanes were aged for up to 21 months under combined gamma irradiation and thermal treatment conditions. A few samples were also placed into actual nuclear storage containers and aged for a similar time period. Experimental techniques, such as FT-IR, NMR, mass spectrometry, TGA, DSC, and tensile tests were employed to characterize two types of polyurethanes, one with and another one without a flame-retardant additive. Our unique aging approach shows that these aromatic polyurethanes are well placed to substitute PVC bags and thus, avoid corrosion of storage metal containers used by the nuclear industry.