Mussel‐inspired decoration of Ni(OH)2 nanosheets on 2D MoS2 towards enhancing thermal and flame retardancy properties of poly(lactic acid)

Abstract

In the present work, a facile and environmental method was developed to fabricate the novel functionalized MoS2 hybrid. Firstly, MoS2 nanosheets were coated with polydopamine (PDA) through the self‐polymerization of dopamine (MoS2‐PDA) in a buffer solution. Then the decoration of Ni(OH)2 on the MoS2‐PDA was synthesized because of the strong affinity of Ni2+ with hydroxyl groups in PDA. Finally, the as‐synthesized MoS2‐PDA@Ni(OH)2 was introduced into poly(lactic acid) (PLA) matrix to explore flame retardancy, thermal stability, and crystalline property of the composites. As confirmed by X‐ray diffraction (XRD), Fourier‐transform infrared spectrometer (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), the MoS2 nanosheets were dually modified with PDA and Ni(OH)2 without destroying the original structures. The thermal degradation of PLA with MoS2‐PDA@Ni(OH)2 generated a notably higher yield of char. Moreover, the crystallization rate of composites is higher than neat PLA. The cone calorimeter test revealed that the introduction of 3% MoS2‐PDA@Ni(OH)2 resulted in lower Peak Heat Release Rate (PHRR) (decreased by 21.7%). Thus, the research provided an innovative functionalization method for manufacturing PLA composites with high performances.