Y. R. Zhi, B. Yu*, A. C. Y. Yuen, J. Liang, L. Q. Wang, W. Yang*, H. D. Lu, G. H. Yeoh
In this article, the polyaniline (PANI)/thermal-exfoliated hexagonal boron nitride (BNO) hierarchical structure (PANI−BNO) was constructed via in situ deposition to improve the dispersion and interfacial adhesion of boron nitride in multi-aromatic polystyrene (PS) and polar thermoplastic polyurethane (TPU). Because of the conjugated structure and polar groups in PANI, the uniform dispersion and strong interfacial adhesion between PANI−BNO and PS and TPU were achieved. Thermogravimetric analysis results showed that the incorporation of PANI−BNO enhanced the thermal stability of PS and TPU, i.e., the temperatures at both 5 and 50 wt % mass loss. In addition, PANI with high charring ability also acted as a critical component to generate a synergistic effect with BNO on reducing the fire hazards of PS and TPU. This well-designed structure led to a remarkable reduction of flammable decomposed products and CO and CO2 yields. Meanwhile, a dramatic decrease in the real-time smoke density and total smoke production was observed for PS and TPU nanocomposites with 3 wt % PANI−BNO hybrids, respectively. The multiple synergistic effects (synergistic dispersion, char formation, and barrier effect) are believed to be the
primary source for these enhanced properties of polymer nanocomposites.