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Intumescent flame retardant poly(butylene succinate) (IFRPBS) composites with enhanced fire resistance were prepared using graphene as synergist. The morphology of fracture surfaces of the composites was investigated by scanning electron microscopy (SEM). The limiting oxygen index (LOI) values increased from 23.0 for the pure PBS to 31.0 for IFRPBS with 20 wt % IFR loading. The addition of graphene further improved the LOI values of the composites and exhibited excellent antidripping properties. The UL-94 V0 materials were obtained with a formulation of 18 wt % IFR and 2 wt % graphene. MFI measurement indicated that the presence of graphene significantly enhanced the melt viscosity and restrained the melt dripping. The thermal degradation and gas products of IFRPBS/graphene systems were monitored by thermogravimetric analysis (TGA), real time Fourier transform infrared spectrometry (RTFTIR), and thermogravimetric analysis-Fourier transform infrared spectrometry (TG-FTIR). X-ray photoelectron spectroscopy (XPS) was utilized to explore the chemical components of the outer and inner char residues.

Epoxy resin (EP)/polyhedral oligomeric silsesquioxane (POSS) hybrids were prepared based on octavinyl polyhedral oligomeric silsesquioxane (OVPOSS) and phosphorus‐containing epoxy resin (PCEP). The PCEP was synthesized via the reaction between bisphenol A epoxy resin (DGEBA) and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO). The structure and morphology of PCEP/OVPOSS hybrids were characterized by Fourier transform infrared spectroscopy and transmission electron microscopy. Differential scanning calorimetry revealed that the PCEP/OVPOSS hybrids possessed higher glass transition temperatures than that of PCEP. The thermal stability of the PCEP/OVPOSS hybrids was studied using thermogravimetric analysis (TGA). The TGA results illustrated the synergistic effect of phosphorus–silicon of flame retardancy: phosphorus promotes the char formation, and silicon protects the char from thermal degradation. The thermal degradation mechanism of the PCEP/OVPOSS hybrids was investigated by real time Fourier transform infrared spectra and pyrolysis/gas chromatogram/mass spectrometry (Py‐GC/MS) analysis. It was found that OVPOSS migrated to the surface of the matrix and then sublimed from the surface in nitrogen; whereas, the vinyl groups of OVPOSS were oxidated to form a radical trap which could react with pyrolysis radicals derived from PCEP to form the branched and crosslinked structure in air. The combustion behaviors of the hybrids were evaluated by micro combustion calorimetry. The addition of OVPOSS obviously decreased the value of peak heat release rate and total heat release of the hybrids. Moreover, scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy were used to explore the char residues of the PCEP and the hybrids. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 693–705, 2010