Biomimetic synthesis of a micro/nano-structured basic magnesium carbonate: Green and highly efficient flame-retardant PBAT composite material

Poly (butylene adipate-co-butylene terephthalate) (PBAT) is a biodegradable and environmentally friendly material. However, due to its flammability and the formation of molten droplets during combustion, green flame retardants need to be added to enhance fire safety while maintaining environmental friendliness. In this work, a rod-shaped magnesium hydroxide carbonate (BMC) was synthesized as a flame retardant and combined with the bio-based phytic acid melamine supramolecular (PM). The micrometer-sized rod-shaped BMC acts as the “corn cob”, while the spherical particles formed by PM supramolecules act as the “corn kernels”. They are structurally locked together through acid-base neutralization, forming a unique “corn-like” hetero-sized assembly structure (PMBMC). When 20 wt% PMBMC is added to PBAT, the composite material passes the UL-94 test and the LOI reaches 28.8 %. Meanwhile, it can reduce PHRR, THR, and MARHE by 82.9 %, 12.2 %, and 69.1 %. Additionally, SP, CO 2 P, and COP are reduced by 92.7 %, 81.3 %, and 82.6 %, respectively. Moreover, compared with the unmodified flame retardant, the Eb and Ts of PBAT/PMBMC increase by 13.6 %, and 51.6 % due to the hydrogen bond. In conclusion, this study provides a new idea for the development of efficient and environmentally friendly PBAT green material flame retardant and smoke suppressant by using natural bio-based materials.