Enhancement of flame retardancy and mechanical properties of polyamide 6 by incorporating melamine cyanurate combined with attapulgite

In this study, the nanocomposites are prepared which used polyamide 6 (PA6) composite as matrix, melamine cyanurate (MCA) as fire retardant and attapulgite (AT) as synergistic agent. The mathematical model between MCA content, AT content, and limited oxygen index (LOI) is established by multiple linear regression fitting. The polymer materials are characterized using Fourier transform infrared spectroscopy, X-ray diffraction, Thermogravimetric Analysis, and scanning electron microscopy. Through response surface methodology, the important variables (polymerization time, the content of MCA, and the content of AT) affecting the mechanical strength of composites are modeled. Results demonstrate that when the t is 0.6 h, the AT content is 6.2%, and the MCA content is 11.5%, the mechanical properties of the PA6/MCA/AT composite are up to 44.81 MPa, and the sample passes the UL-94 V-0 flammability rating, and the LOI reaches 27.9%. Therefore, polymers with highly effective flame retardancy and optimal mechanical properties are prepared. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 47298.