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Herein, piperazine phosphoramide derivatives (PPDO) and titanium carbide modified by hexadecyl trimethyl ammonium bromide (c-Ti3C2) were blended with epoxy resin (EP) to fabricate EP/c-Ti3C2/PPDO nanocomposites. According to thermogravimetric analyzer (TGA) results and pyrolysis kinetic analysis, EP/c-Ti3C2/PPDO nanocomposites can improve the thermal stability and the activation energy of EP. Furthermore, thermal degradation mechanism of EP and its nanocomposites with conversion between 0.55 and 0.99 conforms to the F3 model. With 1 wt% c-Ti3C2 and 3 wt% PPDO incorporated, the LOI value of EP/c-Ti3C2-1/PPDO-3 can reach up to 32% while achieves V-0 rating in the UL-94 test. Based on the cone calorimeter results, the peak heat release rate of EP/c-Ti3C2-1/PPDO-3 reduced by 40.1%. More continuous and dense phosphorus-rich char residues were produced for EP/c-Ti3C2-1/PPDO-3 nanocomposites, which can act as a physical barrier to hinder the heat transfer, protect the underlying polymers from further decomposition and isolate the diffusion of combustible gases. The synergistic effect between c-Ti3C2 and PPDO in catalytic carbonization obviously accounts for the improved flame retardant performance. This work provides an insight into the flame retardant mechanism and the thermal degradation mechanism of c-Ti3C2 and PPDO on EP, showing a promising application potential of c-Ti3C2 and PPDO in enhancing the thermal stability and flame retardancy of EP. [ABSTRACT FROM AUTHOR]

Inflammable characteristic produces an inevitable challenge for the corn storage, which endangers the food demand of human being. We investigated the combustion behavior evolvement of corn under different heat flux, with the aid of cone calorimeter. The reciprocals of square rooted time to ignition presented a linear relation to heat flux (y = 0.0036(q + 11.0833), R2 = 0.8944), similar to other materials. Higher peak values of heat release rate were obtained in heat fluxes of 20 kW/m2 and 25 kW/m2, due to longer heat time and moderate heat flux. Total heat release value was decreased only when heat flux was low to 10 kW/m2 and presented a significant decrease in heat flux of 5 kW/m2 (decreased to 39.0 MJ/m2 from 63.0 MJ/m2). It also found that the ignition temperature for the corn combustion was near 365°C; meanwhile, the surface temperature of corn combustion was higher with higher heat flux. As the XPS analysis presented, the main elements of combustion residue under 35 kW/m2 were C 1s, O 1s, Ca 2p, K 2p, B 1s, and Si 2s. Results from Raman spectra and XRD curves indicated that the graphitization degree of combustion residue was gradually decreased with increase of heat flux. [ABSTRACT FROM AUTHOR]

A novel natural material-based flame retardant melamine chitosan phosphate (MPCS) has been prepared. Its impact on thermal properties and flammability performance of polyvinyl alcohol (PVA) was analyzed. Thermogravimetric analysis data exhibited that MPCS enhanced the thermal stability of materials at high temperature. The results of thermogravimetric analysis/infrared spectrometry (TGA-IR) showed that MPCS decreased the yield of flammable volatilized products greatly. Microscale combustion calorimetry (MCC) data showed that peak heat release rate (PHRR), total heat release (THR) and heat release capacity (HRC) all reduced, which indicated that MPCS improved the flame retardancy of materials. [ABSTRACT FROM AUTHOR]