Facile preparation of modified carbon nanotube‐reinforced PBT nanocomposites with enhanced thermal, flame retardancy, and mechanical properties

In this study, the carbon nanotube was modified by inorganic acids to introduce the carboxylic acid groups on the surface. The modified carbon nanotube ( m ‐CNT)‐reinforced poly(1,4‐butylene terephthalate) (PBT) nanocomposites were prepared through melt blending method. Morphological observations revealed that the m ‐CNT particles were homogeneously dispersed in PBT matrix. Differential scanning calorimeter (DSC) analysis showed that a very small quantity of m ‐CNT can significantly increase the crystallization temperature of PBT. The improvement of thermal stability and tensile strength/modulus of the nanocomposites strongly depended on the uniform dispersion of m ‐CNT and the interactions between m ‐CNT and PBT through hydrogen‐bonding formation. In the cone calorimeter testing, the PHRR decreased from 1189 kW/m 2 for neat PBT to 737 kW/m 2 for PBT/0.9 m ‐CNT containing 0.9 wt% m ‐CNT with a reduction of 38%. The remarkable enhancement of flame retardancy properties was attributed to the condensed‐phase effect acted by the m ‐CNT. POLYM. COMPOS., 37:1812–1820, 2016.