1 Batman University, Vocational School of Technical Sciences, Department of Chemistry and Chemical Processing Technologies, Chemistry Technology Program, Batman, Türkiye
2 Gazi University, Faculty of Technology, Department of Metallurgical and Materials Engineering, Metallurgical and Materials Engineering Division, Ankara, Türkiye
Abstract
This study investigated the effects of triphenyl phosphate (TPP) as a flame retardant and graphite (G) in nanoparticle form on the mechanical, thermal, and flammability properties of expandable polystyrene (EPS) nanocomposite foam. A batch reactor was designed and manufactured. TPP/G/PS nanocomposite beads were produced through suspension polymerization by adding styrene monomer, 20% TPP by weight, 1%, 3%, and 5% nanographite by weight, and other chemicals to the reactor. The PS beads were expanded with n-pentane to turn them into EPS beads, and the EPS beads were subjected to pre-expansion, maturation, molding, and cooling to obtain blocks. The EPS boards obtained from these blocks were exposed to tensile and flexural mechanical tests, TGA tests, UL94, LOI, and cone calorimetry flammability tests according to ASTM and ISO standards. The neat EPS foam began to degrade at 384 °C and was completely consumed. The foams containing TPP and G began to degrade at higher temperatures. In cone calorimetry, the foams containing TPP and G ignited later than the neat foam, the heat release rate decreased as added TPP and G increased, the flame height during combustion decreased as added G increased, and more smoke was produced. It was concluded that the thermal stability and flame-retardant properties of the materials increased.
KOÇYİĞİT, N., & YALÇIN , N. (2026). The Effects of Graphite and Triphenyl Phosphate on the Mechanical, Thermal Stability, and Flammability Properties of Expandable Polystyrene Foam. MAS Journal of Applied Sciences, 11(3), 571–588. https://doi.org/10.5281/zenodo.21621072
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Necati YALÇIN 2