Effect of graphite and common rubber plasticizers on properties and performance of ceramizable styrene–butadiene rubber-based composites

Ceramizable composites are highly filled polymer dispersion composites which create stiff porous and durable ceramic structure when exposed to fire or elevated temperature. However, the incorporation of large amounts of mineral fillers into the composites strongly decreases their processing performance. In order to improve extrusion properties of these composites, plasticizers like triethylamine, ethylene glycol, naphthalene, dibutyl phthalate and graphite were used. Extrudability of the composite mixes was examined as an indicator of their processing performance. After the vulcanization, mechanical properties of the composites were tested. In order to check the micromorphology of the samples scanning electron microscopy was performed. Because of the significant flammability of the plasticizers, it was also important to examine how these additives change combustion behavior of the composites by cone calorimetry. Additionally, composites were ceramized in three different thermal conditions and their compression strength was measured. The incorporation of graphite platelets resulted in optimum balance between enhancing extrudability and preserving satisfactory mechanical properties and ceramization performance. The obtained results showed that ceramizable composites are susceptible to plasticizing and their mechanical and combustibility properties can be preserved like before the plasticizers addition.