Thermal stability, fire behavior, and fumes emission of polyethylene nanocomposites with halogen‐free fire retardants

Abstract

The synergism between nanoparticles and different kinds of halogen-free fire retardants leading to reduction in flammability and smoke generation of polyethylene was investigated. The composites were evaluated by thermogravimetric analysis, oxygen index test, cone calorimeter measurements, and a single-chamber test. Moreover, the semivolatile and volatile compounds evolved in the thermal degradation processes of polyethylene were determined using a steady state tube furnace and gas chromatograph with mass spectrometer. Morphological and structural characteristics as well as thermomechanical properties of the composites were characterized using various techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic mechanical thermal analysis (DMTA). The obtained data were compared to the results received for polyethylene and polymer with bromine-containing fire retardants. The incorporation of nanofillers and halogen-free fire retardants caused a reduction in combustibility as a consequence of the formation of char.Furthermore, the presence of nanoparticles has a beneficial effect on the inhibition of dripping. The polyethylene with carbon nanotubes, zinc borate, and aluminum hydroxide exhibited better combined properties of fire behavior and production of nontoxic smoke compared to the remaining composition and reference materials. K E Y W O R D Scombustibility, fire retardancy, nanocomposites, polyethylene, synergistic effects

Effect of the Addition of Biobased Polyols on the Thermal Stability and Flame Retardancy of Polyurethane and Poly(urea)urethane Elastomers

“…It was observed that the carbonaceous char barrier was created on the surface of the sample. The residue had the form of swollen char and was shaped in layers [ 39 ]. The increased char yield worked as a physical char barrier, which could block the release of degradation volatiles to feed the flame, and thus, the HRR was slowed down [ 40 , 41 ].…”

Production and characterization of ureaurethane elastomers with rapeseed‐based polyol

“…This technique is used for characterization of the mechanical properties of the tested materials. DMTA is a method that measures the stiffness and mechanical damping of a cyclically deformed material as a function of temperature . The curves of the EPUUs annealed at 80 °C obtained from measurements using DMTA are shown in Figs (a), 6(b) and 6(c) for the storage modulus ( E ′), loss modulus ( E ′′) and loss tangent (tan δ ), respectively.…”

“…From analysis of the curve of loss modulus ( E ′′) (Fig. (b)), taking into account the shape, position and height of the peak, it is possible to determine the degree of order and a free movement of the polymer chains . While the modulus E ′ is proportional to the stored energy, modulus E ′′ is part of the energy converted into heat and irreversibly lost .…”

“…6(b)), taking into account the shape, position and height of the peak, it is possible to determine the degree of order and a free movement of the polymer chains. 35 While the modulus E ′ is proportional to the stored energy, modulus E ′′ is part of the energy converted into heat and irreversibly lost. 38 From this curve the relaxation temperature, related to the glass transition temperature of soft segments (T ), was determined as the maximum peak (Table 4).…”

Progress in Biodegradable Flame Retardant Nano-Biocomposites

“…Generally, polymers with an aliphatic backbone will generate a lower amount of smoke than polymers with pendant aromatic groups [ 214 ]. Carbon monoxide (CO), carbon dioxide (CO 2 ) hydrogen cyanide (HCN), hydrogen chloride (HCl), nitrogen oxides (NOx), sulphur dioxide (SO 2 ), aldehydes, polycyclic aromatic hydrocarbons (PAHs) and so forth, are the most common gases developed during thermal decomposition and combustion of polymeric materials [ 215 ]. Since FRs can act in the condensed (polymer breakdown, charring, intumescence) and/or in the gas (gas dilution, chemical quenching of active radicals) phase it is worth noticing that flame inhibition through the gas phase dramatically increases the yield of CO, smoke and toxic gases [ 216 , 217 ].…”