Development of highly performant hybrid materials based on phthalonitrile resin for a simultaneous ballistic and nuclear shielding protection

In this study, a new high-performance hybrid material was designed targeting an efficient ballistic and nuclear shielding protection. To achieve this goal, a typical highly performant thermosetting resin, namely the phthalonitrile (PN) resin, was reinforced with Kevlar fibers (KF-29), as continuous phase, and erbium oxide (Er2O3) nanoparticles, as discontinuous phase. The reinforcing phases underwent a silane surface modification to create a fully connected network aiming an improved stress transfer between the constituents. The mechanical investigations through tensile and bending testing confirmed the positive effect of the addition of an increasing amount (up to 20 wt%) of the Er2O3 nanoparticles. The hybrids also provided excellent gamma rays shielding performances with a screening ratio of about 33% for a 3 cm thick sample. In the meantime, the ballistic tests evaluated under the National Institute of Justice standard (NIJ standard-0101.06-IIA) also highlighted an improved kinetic energy absorption following the increase in the amounts of the discontinuous phase. Overall, this study unraveled for the first time ever the benefits obtained from a fully connected hybrid network in the field of ballistic and radiation protection.