Flammability of Polystyrene with Multiple Flame Retardants: Preparation, Characterization, and Response Surface Methodology Optimization

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Florencio D. de los Reyes Magdaleno R. Vasquez Mark Daniel G. de Luna Peerasak Paoprasert


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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Author Biographies

Florencio D. de los Reyes

Department of Mining, Metallurgical and Materials Engineering, College of Engineering, University of the Philippines Diliman, Quezon City 1101, Philippines

Magdaleno R. Vasquez

Department of Mining, Metallurgical and Materials Engineering, College of Engineering, University of the Philippines Diliman, Quezon City 1101, Philippines

Mark Daniel G. de Luna

Department of Chemical Engineering, College of Engineering, University of the Philippines, Diliman, Quezon City 1101, Philippines

Peerasak Paoprasert

Department of Chemistry, Faculty of Science and Technology, Thammasat University, Rangsit Centre, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand


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