▎ 摘　　要

Poly (Lactic acid) (PLA) as a biodegradable biopolymer is remarkably limited for the engineering applications due to its inherent flammability and brittleness. The conventional polymer toughener and flame retardants severely damaged the environment-friendliness and sustainability of PLA. Particularly, the carbon dioxide (CO2) production from the combustion of PLA composites can easily induce the global warming. In this work, a viable strategy was developed to engineer a dual two-dimension (2D) graphene-derived complex as an effective environment-benign flame retardant and interface modifier for PLA materials. Graphene oxide was first functionalized with sustainable long-chain polyester as a multi-tasking modifier of flame retardant and interfacial compatibilizer. The 2D layered double hydroxide (LDH) was successfully anchored with polyester-functionalized graphene (PG) as a predefined carbonization-catalyzed promoter. The favorable distribution of the dual 2D LDH-anchored PG negated the poor dispersion of high loading LDH, providing PLA matrices with desirable toughness and engineered functional features. The experimental results revealed that the dual 2D graphene-derived complex could enhance flame retardancy with the heat release rate decreased 50% and 29% for poly(propylidene carbonate)-modified and polybutylene succinate-modified composites. The smoke production rate, total smoke production and CO2 production rate of PLA binary composites were also reduced significantly, which could benefit the environment protection. The developed strategy of eco-friendly dual 2D graphene-derived flame retardant not only provided a new insight into modifying the brittle polymer matrices for the functional exploration but also a cleaner process for biodegradable composites with exceptional smoke suppression and reduced carbon dioxide emission. (C) 2020 Elsevier Ltd. All rights reserved.