Direct fabrication of poly(p-phenylene terephthalamide) aerogel and its composites with great thermal insulation and infrared stealth

Abstract Limited processability of high molecular weight poly(p-phenylene terephthalamide) (PPTA) results in complex, time-consuming, and high-cost procedure of preparing PPTA aerogel. Herein, the chopped PPTA fiber reinforced PPTA aerogel was prepared by spontaneous low molecular weight PPTA (LMW-PPTA) gel. The pore structure and thermal insulation characteristics of composite PPTA aerogel were effectively controlled by varying the concentration of LMW-PPTA solution. Then, the PPTA/phase-change composite (PPTA/PCM) was obtained by dipping process. It was confirmed that the composite PPTA aerogel acquired superior thermal insulation, mechanical properties and great thermal stability above 500 °C. Furthermore, the infrared stealth property of PPTA/PCM composite material was also studied systematically. Significantly, the facile-procedure and lower-cost PPTA aerogel and its composites may have a great potential to be applied as thermal insulation and infrared stealth materials in industrial applications.