Thermal Stability, Fire and Smoke Behaviour of Epoxy Composites Modified with Plant Waste Fillers

Abstract

The influence of plant fillers on the flammability and smoke emission of natural composites was investigated. Epoxy composites with 15, 25, and 35 wt % of walnut and hazelnut shell, as well as sunflower husk, were prepared and examined. The ground organic components were characterized by grain size distribution, thermogravimetric analysis (TGA) and microstructure observations (SEM). The composite materials were subjected to dynamic mechanical analysis (DMA) and structural evaluation with scanning electron microscopy. Cone calorimeter tests and TGA determined the influence of plant waste filler addition on thermal stability and flammability. Moreover, the semi-volatile and volatile compounds that evolved during the thermal decomposition of selected samples were identified using a steady state tube furnace and a gas chromatograph with a mass spectrometer. The intensity of the degradation reduced as a function of increasing filler content, while the yield of residue corresponded to the amount of lignin that is contained in the tested plants. Moreover, the incorporation of agricultural waste materials resulted in the formation of a char layer, which inhibits the burning process. The yield of char depended on the amount and type of the filler. The composites containing ground hazelnut shell formed swollen char that was shaped in multicellular layers, similar to intumescent fire retardants.

Curing and thermal properties of tannin-based epoxy and its blends with commercial epoxy resin

“…There have been many literature reports about modification of epoxy resin using various types of bio-based materials, for examples, clay [5], lignin [6], plant seed oils [7], Eugenol [8], vanillin [9], plant waste filler [10], cellulose nanofibrils [11] and others. The use of natural materials (mainly bio-phenolic types) in epoxy technologies providing similar properties to those of synthetics materials such as modulus, curing and mechanical strength is still a highly important challenge.…”

The influence of oil content within lignocellulosic filler on thermal degradation kinetics and flammability of polylactide composites modified with linseed cake

“…The analysis of the MAHRE during the cone calorimetry test allows to evaluate the fire behavior of a material in full‐scale conditions. [ 42 ] The composites show MARHE values notably higher than in the case of pure PLA. However, once again, no correlation between the oil content and the cone calorimetry test results can be noticed in this case.…”

Thermo‐mechanical properties of rosin‐modified o‐cresol novolac epoxy thermosets comprising rosin‐based imidoamine curing agents

“…For comparison, El‐Ghazawy et al [ 25 ] reported the thermal behavior of commercial epoxy resin (DGEBA) and rosin‐based epoxy resin (TGK) isothermally cured with a p‐phenyl diamine, a commercial crosslinker, that exhibited IDT at 255°C and 260°C, respectively, and T max at 312°C and 287°C, respectively. Salasinska et al [ 38 ] have also reported thermal analysis of commercial bisphenol A‐based epoxy resin cured with isophorone diamine crosslinker. The epoxy system showed 5% and 10% weight loss at 172°C and 224°C for the resin system.…”