Main Article Content
The flammability of polystyrene (PS), compounded with silica nanoparticles (SiNPs), 9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide (DOPO), and melamine as flame retardants was studied. Surface modification of SiNPs using three silane coupling compounds, 3-aminopropytriethoxy silane (APTES), phenyltriethoxy silane (PHTES), and n-propyltriethoxy silane (PTES), was performed. The flammability of PS, characterized by the limiting oxygen index (LOI), reduced when the flame retardants were added. DOPO exhibited the best flame retardant property, increasing the LOI value of the PS by 42.4 %. A quadratic model for LOI was developed using D-optimal design with the percentage loading of APTES-modified SiNPs, DOPO, and melamine as the independent variables. The response surface methodology was used to explain the synergistic effects of these flame retardants. As the percentage loadings were increased, the observed increase in the LOI value was attributed to both the main effects and interaction effects of the flame retardants.
Keywords: rice husk; silica nanoparticle; polystyrene; flame retardant; surface modification
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