Molecular dynamics simulation of the 3-15alkyphenol compatibilizer in highly toughened and robust polyamide 10,12/MWCNT composites.

Abstract

Highly toughened and stiff polyamide 10,12 (PA10,12) composites present a promising alternative to metal products for high-impact environments. However, it is challenging to toughen PA10,12 composites without compromising their robustness. Herein, we report a facile and scalable route to simultaneously develop reinforced and toughened PA10,12 composites via compounding PA10,12, carbon nanotubes (CNTs) and 3-15alkyphenol (PDP). The PDP acted as a compatibilizer to well-disperse MWCNTs since they tended to be adsorbed onto the CNT surface, which was revealed by molecular dynamics simulation. According to the simulation statistics, the vertical PDP conformations (to the CNT surface) were predominant in the ternary composites with ∼78.7% probability. Moreover, the hydrogen bonds (H-bonds) between the PDP and the PA matrix were confirmed using FTIR. A crystallization kinetics study also revealed that the crystallization temperature increased from 166.7 °C for the neat PA10,12 to 168.7 °C for the ternary PA/PDP/CNT composites containing 1.5 wt% CNTs, while the crystallization half-time increased from 0.58 s for the neat PA10,12 to 1.2 s for the ternary composites. It was also found that the notched impact strength of the ternary composites reached 75.2 kJ m-2, which was 970% higher than that of the neat PA10,12 without compromising their tensile strength of 50.5 MPa much. This work provides a new insight into PDP as a compatibilizer to develop simultaneously stiff and toughened nylon composites.