Facile and scalable fabrication of bioderived flame retardant based on adenine for enhancing fire safety of fully biodegradable <scp>PLA</scp>/<scp>PBAT</scp>/<scp>TPS</scp> ternary blends
Juan Qi, Yingtong Pan, Zhonglin Luo, Biaobing Wang
Abstract
Abstract The facile fabrication of a bioderived flame retardant (marked as ATMP‐A) via ionic exchange between adenine and amino trimethylene phosphonic acid was reported in the present work. The incorporation of ATMP‐A endows the poly lactic acid (PLA)/poly butylene adipate‐co‐terephthalate (PBAT)/thermoplastic starch (TPS) ternary blends with improved fire safety without negatively affecting the biodegradability. The PLA/PBAT/TPS blend containing 18 wt% ATMP‐A alone achieves a UL‐94 V‐0 rating with a higher LOI value (28%). Meanwhile, its peak of the heat release rate and total heat release are reduced by 60.5% and 34.1% as compared with the PLA/PBAT/TPS ternary blend, respectively. Such excellent flame retardancy is mainly attributed to the formation of the intumescent flame retardant system in which ATMP‐A acts as both acid and gas sources together with TPS as a natural carbon source. Based on the analysis of the volatile gases and the char residues, a possible flame retardant mechanism including gas phase and condensed phase is proposed. This work provides a novel and effective idea for improving the fireproof performance of PLA/PBAT/TPS blends and will broaden its practical application fields, such as, agricultural film and packaging fields.