Flame Retardant Properties Of Samples Research Articles

The synergistic effects of a novel intumescent flame-retardant poly-(4-nitrophenoxy)-phosphazene and ammonium polyphosphate on ABS systems

Novel intumescent flame retardancy acrylonitrile–butadiene–styrene (ABS) composites were prepared by adding poly-(4-nitrophenoxy)-phosphazene (DPP) as charring and inflate agent, and ammonium polyphosphate (APP) as acid and inflate agent. The flame-retardant properties of samples were studied by LOI, UL-94 and microscale combustion calorimeter (MCC), when the ratio of APP and DPP was 1:1 with 30 mass% additive amount, the LOI was 27%, and the UL-94 reached V-0 rating. To further study the synergistic effects of DPP and APP, the charring-forming capability and thermal behavior of ABS composites were extensively studied by thermogravimetric analysis (TGA) under nitrogen and air, respectively. Also the binary system of APP and DPP was investigated by TGA measurements to identify their reaction and the synergistic mechanisms. The char residues were studied by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) analysis and Fourier transform infrared (FTIR). Meanwhile, the gaseous products generated in degradation process were detected by thermogravimetric analysis coupled Fourier transform infrared (TGA/FTIR).

Inherently flame-retardant flexible bio-based polyurethane sealant with phosphorus and nitrogen-containing polyurethane prepolymer

A novel phosphorus and nitrogen-containing flame-retardant polyurethane prepolymer (FRPUP) was successfully synthesized and characterized by FTIR, 1H NMR, and 31P NMR. The flame-retardant polyurethane sealants (FRPUS) were prepared by curing FRPUP with castor oil. The flame-retardant properties of samples were investigated by the limiting oxygen index and cone calorimeter testing (CCT). The results showed that FRPUP can improve the flame retardancy of polyurethane sealants (PUS). The thermal decomposition behavior of the PUS was investigated by thermogravimetric analysis. Moreover, the thermal degradation mechanisms of FRPUS were investigated by thermogravimetric analysis/infrared spectrometry, FTIR, and X-ray photoelectron spectroscopy. The results indicated that the good flame retardancy of FRPUS can be attributed to the synergistic effect of phosphorus and nitrogen in FRPUP.

Preparation, Flame Retardancy, and Thermal Degradation of Unsaturated Polyester Resin Modified with a Novel Phosphorus Containing Acrylate

A novel reactive phosphorus-containing acrylate (ODOPB-AC) was successfully synthesized and characterized, and the flame retardant unsaturated polyester resins (FR-UPR) with various amounts of ODOPB-AC were prepared. The thermal decomposition and flame retardant properties of samples were investigated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), and microscale combustion calorimetry (MCC). As the ODOPB-AC content increased, the LOI value of FR-UPR was increased, while the value of peak heat release rate (PHRR) and total heat release (THR) were reduced. The evolved gas analysis and condensed thermo-oxidative degradation process of UPR and FR-UPR were monitored by thermogravimetric analysis/infrared spectrometry (TG-IR) and real-time infrared spectrometry (RT-IR), providing insight into the thermal degradation mechanism. ODOPB-AC acted in the gas phase through flame inhibition and in the condensed phase through charring. Moreover, scanning electron microscopy (SEM) and X-ray photoelectr...

Studies on the flame retardant, mechanical and thermal properties of ternary magnesium hydroxide/clay/EVA nanocomposites

Ethylene vinyl acetate copolymer (EVA) nanocomposites were prepared by melt blending of EVA with nano-sized magnesium hydroxide [Mg(OH)2] and modified montmorilonite clay. Nano Mg(OH)2 was synthesized in the laboratory by matrix-mediated growth and controlled technique. Particle size of Mg(OH)2 crystals was performed using X-ray diffraction technique and was found to be in nanometer range. Ternary EVA, clay and Mg(OH)2 nanocomposites were prepared by melt blending using Brabender Plastograph EC. The prepared samples were characterized by flame test, tensile tests and thermogravimetric analysis (TGA). Morphological study of the composites was studied by scanning electron microscopy (SEM). Flame retardant properties of samples were significantly improved in the EVA/clay/Mg(OH)2 nanocomposites without losing its mechanical properties. Ternary system showed better thermal, flame retardant and mechanical properties compared with nanocomposites of EVA filled only with the nano Mg(OH)2.