Preparation and Performance Study of <scp>CR/PPTA‐Pulp</scp> Composites Modified With Rare Earth <scp> CeO ₂ </scp>

ABSTRACT With the rapid development of aerospace technology, solid rocket motors have put forward higher requirements for the comprehensive performance of insulation materials. Chloroprene rubber (CR) is widely regarded as an ideal matrix for thermal insulation materials due to its excellent tensile strength, high elongation at break, and good flame‐retardant properties. In this study, a flexible and ablation‐resistant composite insulation material was prepared by adding nano cerium oxide (CeO 2 ) to the CR/poly‐p‐phenylene terephthamide pulp (PPTA‐pulp) composite matrix, and the effect of CeO 2 on its mechanical and ablation‐resistant properties was systematically studied. Based on this, a three‐component thermal conductivity model of CR/PPTA‐pulp/CeO 2 was constructed, and molecular dynamics simulations were carried out with Reverse Non‐Equilibrium Molecular Dynamics (RNEMD) to predict its thermal conductivity. The results show that when the amount of CeO 2 is added at 0.25 phr, the tensile strength and elongation at break are increased by 25.9% and 17.6%, respectively, while the linear ablation rate and thermal conductivity are reduced by 52.0% and 16.9%, respectively. The positive role of CeO 2 in enhancing the ablation performance of materials was confirmed by molecular dynamics simulation.