In this study,the effect of hot calendering process on the microstructure and properties of poly(p-phenylene terephthalamide)(PPTA) paper-based materials was investigated.The microstructures of the fracture surface,crystalline structure,and single fiber strength of the PPTA paperbased materials as well as the different bonding behaviors between the PPTA fibers and PPTA fibrids obtained before and after the hot calendering process were examined.The results indicated that a high linear pressure would result in a limited improvement of the strength owing to the unimproved paper structure.The optimal values of tensile index and dielectric strength of 56.6 N·m/g and 27.6 kV/mm,respectively,could only be achieved with a synergistic effects of hot calendering temperature and linear pressure(240℃ and 110 k N/m,respectively).This result suggested it was possible to achieve a significant reinforcement and improvement in the interfacial bonding of functional PPTA paper-based materials,and avoid the formation of unexpected pleats and cracks in PPTA paper-based materials during the hot calendering process. In this study, the effect of hot calendering process on the microstructure and properties of poly (p-phenylene terephthalamide) (PPTA) paper-based materials was investigated. The microstructures of the fracture surface, crystalline structure, and single fiber strength of the PPTA paperbased materials as well as the different bonding behaviors between the PPTA fibers and PPTA fibrils obtained before and after the hot calendering process were examined.The results indicating that a high linear pressure would result in a limited improvement of the strength due to the unimproved paper structure The optimal values ​​of tensile index and dielectric strength of 56.6 N · m / g and 27.6 kV / mm, respectively, could have been achieved with a synergistic effect of hot calendering temperature and linear pressure (240 ° C and 110 kN / m, respectively). This result suggests it was possible to achieve a significant reinforcement and improvement in the interfacial bonding of functional PPTA paper-based materials, and avoi d the formation of unexpected pleats and cracks in PPTA paper-based materials during the hot calendering process.