Preparation of core-shell melamine cyanuric based flame retardant for improving comprehensive performance of polyamide 56

•BP-MCA is applied to improve the comprehensive performance of PA56.•The PA56 system shows superior flame retardant and mechanical properties.•BP-MCA exhibits smaller diameter and larger aspect ratio compared with MCA. The preparation of flame retardant PA56 material with superior thermal stability, melt-drop resistance, and mechanical properties has been challenging in industry. Herein, we prepared a core-shell MCA-based flame retardant (BP-MCA) for PA56 via the hydrogen bond self-assembly and solvent exchange strategies. The hydrogen bond self-assembly strategy modulates the morphology of MCA-based flame retardant. The solvent exchange strategy further improves the dispersion, and char-forming properties of flame retardant. Compared with PA56, PA56/BP-MCA achieves the UL-94 V-0 rating, LOI value of 32.5 % and THR value of 55.2 MJ/m2. Besides, PA56/BP-MCA exhibits superior mechanical properties due to the larger aspect ratio and better dispersion of BP-MCA.