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The aggregation and plasticizing of most 9,10-dihydro-9-oxa-10-phosphaphenanthrene −10-oxide (DOPO) derived additives often result in deteriorating the glass transition temperature and mechanical properties of epoxy resins (EP). To address this issue, an imide-DOPO derivative (BMP) with bulky aromatic structure was successfully synthesized. Benefitting from the space hindering and intermolecular interaction (π-π stacking) of BMP, it does not lead to the loss of glass transition temperature, and only a minor damage of tensile and impact strengths is caused. Additionally, with only 0.78 wt% loading of phosphorus (10 wt% BMP), the EP/BMP 10% achieves UL-94 V-0 and high LOI value of 35%. Simultaneously, both the heat release rate and total smoke production are markedly reduced. More excitingly, BMP exhibits aggregation-induced emission enhancement of fluorescence in the N, N -dimethylformamide/water mixed solution as well as epoxy resin. This work provides a new insight in simultaneously imparting flame retardancy and fluorescence to epoxy resins without losing glass transition temperature. [Display omitted] • Imide-DOPO derivative exhibits aggregation-induced emission enhancement. • Imide-DOPO derivative endows epoxy resin with excellent flame retardancy. • No loss of T g while the improvement of flame retardancy. • Fluorescence is imparted to the flame retardant epoxy resin. [ABSTRACT FROM AUTHOR]

The SiO 2 @metal organic framework (Universitetet i Oslo-66, UiO-66) core–shell microspheres were constructed through covalent linkage between amine groups in UiO-66-NH 2 and epoxy groups on the surface of silica. The morphology and size of the SiO 2 @UiO-66 core–shell microspheres could be simply controlled by tuning the ratio between UiO-66-NH 2 and epoxy terminated silica (E-SiO 2). As observed by TEM, the SiO 2 @UiO-66 hybrids showed better dispersion state within epoxy matrix compared to either E-SiO 2 or UiO-66-NH 2. The incorporation of SiO 2 @UiO-66 hybrids slightly promoted the thermal degradation of the resultant epoxy composites but improved residual yield. The dynamic mechanical analysis results indicated that the SiO 2 @UiO-66 hybrids slightly increased the glass transition temperature and the modulus. The SiO 2 @UiO-66 hybrids exhibited higher efficiency in reducing the heat release rate and the smoke production rate compared to either E-SiO 2 or UiO-66-NH 2. The influence of the component ratio in SiO 2 @UiO-66 on flame retardancy of the epoxy composites was also studied by cone calorimeter. Specifically, the SiO 2 @UiO-66 hybrid with medium ratio (SiO 2 @UiO-66-2) exhibited maximum reduction in peak heat release rate (−31%), total heat release (−23%) and total smoke production (−16%). The char residues were investigated by the Fourier transform infrared spectra, scanning electron microscopy and X-ray photoelectron spectroscopy, which demonstrated that the enhanced flame retardancy of EP/SiO 2 @UiO-66-2 was attributable to the continual morphology and high thermal resistance originated from the presence of the silicon and zirconium complex. These favorable characteristics including high flame retardant efficiency and good smoke suppression make SiO 2 @UiO-66 hybrids promising for flame retardant polymers application. • The SiO 2 @UiO-66 hybrids showed core–shell microsphere structure. • The addition of 3 wt% SiO 2 @UiO-66-2 caused 31% reduction in peak heat release rate. • The addition of 3 wt% SiO 2 @UiO-66-2 led to 16% reduction in total smoke production. [ABSTRACT FROM AUTHOR]