Papers by Keyword: Flame Retardant

Abstract: This paper, investigated the effects of expandable graphite and ammonium polyphosphate on the flame-retardant properties of nitrile butadiene rubber. Several formulations of NBR were prepared by combining different ratios of expandable graphite and ammonium polyphosphate to evaluate their synergistic flame-retardant effects. The results show that the combination of expandable graphite and ammonium polyphosphate significantly enhances the flame-retardant effects of nitrile butadiene rubber, as evidenced by improved limiting oxygen index values, horizontal burning rates decreased and passed the UL-94 V1 when the ratio of expandable graphite and ammonium polyphosphate as (2/1). Results from TGA demonstrated that the ammonium polyphosphate/expandable graphite combination could retard the degradation of rubber by promoting the formation of a compact char layer on the condensed phase surface. This char layer effectively protects the matrix from heat penetration and the diffusion of flammable gas products, resulting in better flame-retardant performance. The effect of flame retardant on the mechanical properties of nitrile butadiene rubber was also evaluated. The results showed that the mechanical properties decreased with increasing flame retardant content.

Abstract: In polymer studies, biocomposite now draws attention as an exciting material obtained from combining natural fiber and matrix, which is an environmentally friendly material with biodegradable properties. One of the natural fibers often used in polymer filler is banana stem fiber. This study aims to prepare carbon-coated waste-dried banana fiber. The waste of banana stems was used as raw material for preparing cellulose-rich banana stem fiber. The banana fiber was soaked in an alkaline solvent, 1% NaOH, to remove the lignin content. The dried banana fiber was then coated with activated carbon and graphite by immersion in the carbon dispersion in ethanol with PVA glue binder added. Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) spectra show different profiles on raw and carbon-coated banana fibers, indicating successful carbon coating. The burning test and thermal analysis results show that carbon-coated banana fibers have better thermal properties than raw banana fiber. This suggests that carbon covered on the fiber surface could enhance its thermal property due to intramolecular bonds between fibers and carbon particles. Graphite-coated banana fibers have the longest burning time and are concluded to have the best fire-retardant properties among all samples. The findings confirmed the potential use of carbon-coated banana fiber as filler material for reinforcing conventional composites.

Abstract: The effect of zinc stannate and synergy between zinc stannate with ammonium polyphosphate in polypropylene matrix is studied. The zinc stannate nanoparticles were synthesized by surfactant assisted low temperature precipitation method, and further surface modified with tetraethyl-orthosilicate at room temperature. Zinc stannate (ZS) and ammonium polyphosphate (APP) were incorporated in polypropylene matrix (1, 5 and 10 % by wt.). PP nanocomposites were analysed for flexural strength, tensile strength, linear burning rate, smoke density and LOI test. Morphology of nano particles and composites were analysed by FESEM. Mechanical analysis of PP nanocomposites demonstrates that, the modified ZS-TEOS performed better than unmodified ZS. Smoke density profiles suggest that the APP could slightly generate more smoke in PP with ZS and ZS-TEOS. Linear burning rate test results indicates that the APP with ZS and ZS-TEOS provide stability to PP for resisting flame spread.

Abstract: Digital light processing (DLP) technology has been developed based on stereolithography (SLA) 3D-printing principle. The biodegradable and low-cost polylactic-acid (PLA) has so far been used as polymeric material for photopolymer resin in SLA and DLP. To achieve functional SLA-processed product, the properties of such PLA has been improved, with the aim to make it flame retardant, less viscous, and having light transmittance characteristics. In this study, the liquid raw PLA photopolymer was changed by adding different contents of Ammonium Phosphate (APP), melamine cyanurate (MCA), Aluminum Tri-hydroxide (Al₂O₃) and Nano-silicon dioxide (SiO₂) additives. The solid PLA nanocomposite specimens were printed by using DLP device according to the standard geometry for burning test UL-94 to evaluate its flame-retardant property. In addition, the printing product and residue after burning test was analyzed for their morphological characteristic by using SEM. The results showed that the low weight fraction of MCA showed excellent performance. PLA/MCA successfully kept green body form until the sintering temperature of stainless steel was achieved. It can become a reference for application DLP 3D printing products in the casting and sintering process.

Abstract: Phase Change Materials (PCMs) have attracted growing attention recently in the renewable energy utilization and building energy efficiency due to their high capacity for storing thermal energy but their applications have been restricted by leakage, poor thermal conductivity, and high flammability. In this work, the flame retardant phase change material has been successfully prepared through integrating Resorcinol bis (diphenyl phosphate) (RDP) as a flame retardant into lauric acid (LA) as a phase change material. The DSC (differential scanning calorimeter) test is used to measure the thermal properties of LA_RDP. The thermogravimetric analysis (TGA) test demonstrates that the thermal stability of composite LA_RDP is improved. Cone calorimeter is applied to study the flammability properties of the flame retardant phase change material. As a result, the RDP-based flame-retardant PCMs developed could be used for safe and efficient solar energy storage applications.

Abstract: The heat-induced behavior of strength characteristics demonstrated by a “steel – wood” composite has been studied. The study has revealed the bending strength of steel plates in contact with a wooden bar is maximal if treated by a flame retardant agent containing phosphorous and urea solution.

Abstract: Systems of floor insulation on the ground, isolation of roads and shallow foundations suggest the use of heat-insulating products resistant to moisture, the minerals contained in it, having low heat conductivity and water absorption and relatively high strength for compressive loads.The aim of the research was to study the possibility of using mineral substances containing crystalline water as a dispersed component. Firstly, such compounds as a reinforcing component increase the strength characteristics of products. Secondly, being flame retardants, they contribute to increasing the fire safety of materials and building systems in which these materials are used. To achieve this goal, two particular tasks were set: determination of the optimal consumption of mineral modifying additives; assessment of exploitative stability of the received products. It was found that the introduction of a mineral modifying additive can significantly increase the compressive strength by 10% deformation of samples from extruded polystyrene foam. The exploitative stability of products with a mineral additive varies slightly and depends on its consumption and uniform distribution in the product matrix. The effect of additive consumption on the change in the thermal conductivity of products has not been established. A nomogram has been built which allows one to evaluate the properties of products and determine the optimal consumption of a modifying additive.Systems of using products from modified extruded polystyrene foam in monolithic foundations with insulation for buildings erected on problem soils are considered.

Abstract: Development of multifunctional flame retardant (FR) polymer composite was done. Flame retardant polymer composite was prepared by modifying diglycidylether of bisphenol-A (DGEBA) epoxy. Modification involved two types of FR. Reactive type FR used was phosphoric acid and additive type FR used was magnesium hydroxide. Composite was fabricated using resin infusion under flexible tooling (RIFT) process. Different FR epoxy samples were evaluated by compression test, UL 94. The carbon fiber reinforced polymer composite with attributes of flame retardancy were characterized using in-plane shear test, to estimate the structural properties, and UL-94 test, to estimate the fire performance. FR composite exhibited UL-94 rating of V-1 and a shear modulus of 9.7 GPa, which proved it to multifunctional.

Abstract: In scientific work is presented the solution of scientific and practical task – the development and evaluation of the possibility of using difficult combustible epoxyurethane (EU) mastic with increased vibration-damping properties and the necessary physical and mechanical properties for cladding the internal metal surfaces of railway rolling stock bodies. The compositions of the developed mastic based on the mixture of oligester cyclo-cab (OCC) and epoxidian (ED) oligomers with the addition of flame retardant – ammonium polyphosphate (APh), as well as hydrophobic filler methylaerosil AM-1-300 to give the composition thixotropic properties. As a result of dynamic-mechanical and viscoelastic researches, it was found that the mastic composition ED: OCC with the content of fire-retardant additive and thixotropic filler has high damping properties (tgδ = 0.45-0.47) in highly elastic field, and therefore, from practical point of view, this the material can work both at low (from -60°C) and moderate temperatures (to +60°C). A comprehensive fire hazard assessment showed that the developed mastic belongs to the group of difficult combustible and difficult flammable materials with slow flame spread and moderate smoke generating ability, as well as moderately hazardous in terms of toxicity. The achieved level of characteristics of the difficult combustible vibration damping mastic testifies about the prospects of its further use for facing the internal metal surfaces of bodies of railway rolling stock in order to ensure their fire safety and acoustic comfort.

Abstract: The jute and polypropylene fiber (PP) were formed into jute/PP composite by carding, netting and needling. Using surface dusting process, β-CD and ammonium phosphate (APP) were combined and hot pressed to form a flame-retardant layer on the surface of jute/PP composite. The results show that the thermal compression film formation on the surface of jute/PP composite after β-CD and APP compounding can significantly improve the flame retardancy and thermal stability of the jute/PP composite. When the mass ratio of β-CD to APP is 1:2 and keeping the 20wt% total content of the flame retardants, the jute/PP composite becomes extinguished after 58s combustion. The limiting oxygen index (LOI) value is 26.6%, which reaches the third fire resistance according to Japan's JISD 1201-77 standard. The heat release rate and effective combustion calorific show the lowest value and the carbon residual at 700°C is increased by 11. 68%.