Thermal decomposition of fire-retarded high-impact polystyrene and high-impact polystyrene/ethylene–vinyl acetate blend nanocomposites followed by thermal analysis

Abstract

Blend nanocomposites of high-impact polystyrene and ethylene–vinyl acetate at a ratio of 3:1, with the addition of aluminum hydroxide Al(OH)3 and diphenyl 2-ethylhexyl phosphate (DPO) as fire retardants (FRs) and silica (SiO2) nanofiller were prepared by extrusion. Thermal decomposition, mechanism and kinetics of degradation of the studied samples were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The fire-retarded samples were characterized by following the degradation kinetics obtained from TGA data by recording the samples at four different heating rates. That enables us to determine one of the kinetic parameters, activation energy (E a) of thermal decomposition. The effect of high concentration of FRs on morphology and properties of the studied samples were analyzed by scanning electron microscopy and mechanical properties. The obtained results show that the FRs delay thermal decomposition, particularly in combination with SiO2 nanofiller, which significantly contributes to slowing down the degradation process.

Application of waste silicon rubber composite treated by N2 plasma in the flame‐retardant polypropylene

“…It is clear that there are two steps curves for WSiRC, ASiR, and PLSiR: first degradation temperature range (200–300 °C) and second degradation temperature (300–550 °C). As for the original WSiRC, the weight loss at the range of 200–300 °C is ascribed to the dehydration of Al(OH) 3 . The similar weight losses are also found in the curves of ASiR and PLSiR, but those are much smaller than that of the original WSiRC.…”

Kinetic Study of Thermal Degradation of High-impact Polystyrene Nanocomposites with Different Flame Retardants using Isoconversional and Model Fitting Methods

“…All fire retarded samples generally have lower average Ea values (in the region α = 0.2-0.9) than pure HIPS which could lead to conclusion that HIPS has higher thermal stability and slower degradation rate. Our previous studies [1,3,32] show that is not the case. Since Ea is only one part of kinetic triplet, it is possible that difference in frequency factor, A, of composites compensates their lower Ea when compared to HIPS.…”

“…Lower values of Ea of fire retarded composites were overcompensated by the difference in A by a magnitude of four to five compared to HIPS thus giving overall slower degradation rate and higher thermal stability which is in accordance with previous research. [1,3,32] It seems from Figure 5 that sample PS-20AP-4C starts to degrade earlier than pure HIPS, but it has to be taken into account that it has weight residue at 500 °C of 20 % a) b)…”

“…Due to its chemical constitution HIPS is highly flammable and therefore different flame retardants (FR) are added to HIPS to reduce its flammability which has been described in many studies. [1][2][3][4][5] Addition of flame retardants to polymers increases their flame resistance but also changes kinetics of decomposition which has been in focus of many papers. [6][7][8][9][10] The kinetic modelling of the decomposition is crucial for an accurate prediction of the materials behaviour under different working conditions.…”

Thermogravimetric kinetics of degradation of HDPE based MWCNTs reinforced composites

“…However, it is important to note that the activation energy obtained for composite with higher volume fraction loading of MWCNTs (viz.,~0.0044) is nearly constant, as calculated using all the iso-conversional approaches discussed above. This constancy of E a with conversion rate (α) between 0.2 and 0.8 suggests a single-step degradation based reaction [51] that appears to be commenced by random scission mechanism. Therefore, HDPE/MWCNTs composites with volume fraction loading of MWCNTs (between 0.0011 and 0.0033) follow diffusion based mechanism (viz., D2, D3 and D4) and for composites with MWCNTs volume fraction (≥0.0044) follows a first order reaction mechanism (F1-model), which is consistent with CR integral model fitting analysis.…”