A phosphorus abundant biomass phytic acid (PA)-functionalized metal−organic framework (MOF) UiO-66-NH 2 (PA-UiO66-NH 2 ) was synthesized successfully as a novel fire retardant (FR) to reduce fire hazards and suppress smoke for the epoxy (EP) resin. The complexing and salt formation reaction between phosphate groups and both Zr species or amine groups on UiO-66-NH 2 were verified by Xray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The EP/5PA-UiO66-NH 2 sample exhibited excellent fire retardancy and toxic gases suppression property with a 41% decrease in the peak heat release rate and a 42% reduction in total smoke production. The slightly modified thermal degradation path of the EP/5PA-UiO66-NH 2 sample was evidenced by means of pyrolysis gas chromatography−mass spectrometry, which led to the reinforced char with a strong barrier and a higher polyaromatic structure. Moreover, the amine and phosphorus groups may react with EP, thus providing a better interfacial strength between FRs and EP matrix. Therefore, the enhanced mechanical property was also observed by dynamic mechanical analysis with a light increment of storage modulus (8%). In perspective, functionalization of MOFs to modify the thermal decomposition of FR may provide a possible way for MOFs to become efficient FRs.

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Based on the biodegradable material-polyethylene glycol (PEG)-as the plasticizer, oxidized wood flour (OWF) as the charring agent for polylactide (PLA), a series flame-retardant PLA biocomposites were prepared via melt-compounding and hot-compression. The effect of OWF on the thermal, mechanical and flame retardant properties of biocomposites was investigated systemically. We have found that after the incorporation of PEG and OWF with 10wt% into PLA, the biocomposite showed higher tensile elongation than pure PLA. Furthermore, the presence of OWF and ammonium polyphosphate (APP) imparted the biocomposite good flame-retardant performance, shown a remarkable reduction on the peak of heat release rate (PHRR), improved LOI value and passed UL94 V-0 rating. Moreover, Scanning electron microscopy-energy dispersive spectra (SEM/EDS) and thermogravimetric analysis coupled with infrared spectrometer (TG-FTIR) were also performed to understand the flame retardant 2 mechanism. These results proved that OWF could be as new functional filler for polymer composites to further improve their flame retardancy.