Atom-economic synthesis of an oligomeric P/N-containing fire retardant towards fire-retarding and mechanically robust polylactide biocomposites

• Published in: Journal of materials science & technology Vol. 160; pp. 86 - 95
• Main Authors: Feng, Jiabing, Lu, Yixia, Xie, Hongyan, Zhang, Yan, Huo, Siqi, Liu, Xiaohuan, Flynn, Matt, Xu, Zhiguang, Burey, Paulomi, Lynch, Mark, Wang, Hao, Song, Pingan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10.10.2023
• Subjects: Atom economy; Fire retardant; Mechanical properties; Polylactide; Mechanical properties; Polylactide; Atom economy; Fire retardant
• ISSN: 1005-0302; 1941-1162
• DOI: 10.1016/j.jmst.2023.04.003

•Atom-economic synthetic strategy of a P/N fire retardant (APN) is developed.•3 wt% APN significantly improves the fire safety of PLA.•The toughness of PLA increases by 85% but maintaining its tensile strength. Renewable and biodegradable polylactide (PLA) has excellent mechanical strength but is highly flammable which restricts its practical applications. Many phosphorus/nitrogen (P/N)-based flame retardants are effective in PLA, but their high addition loading usually decreases the mechanical strength of the PLA bulk. For polyphosphoramides, despite high fire-retardant efficiency, their chemical synthesis often generates chemical wastes as byproducts. Herein, we report an atom-economic and highly efficient oligomeric P/N fire retardant (APN) prepared using a mild Michael addition polymerization with no byproducts. Using only 3 wt% APN, the resulting PLA exhibits desired fire retardancy including a UL-94 V-0 rating and a limiting oxygen index of 37.6%. Furthermore, the toughness of the fire-retardant PLA increases by 85% compared to pure PLA, with both tensile strength and thermal stability preserved. This work offers an atom-economic strategy for synthesizing highly efficient P/N fire retardants for use in the creation of fire-resistant PLA with robust mechanical properties. Atom-economic synthesis was developed to synthesizing a P/N-containing fire retardant for creating fire-retardant PLA. [Display omitted]