Polystyrene nanocomposites with improved combustion properties by using TMA-POSS and organic clay

Nowadays, novel nanocomposites including polyhedral oligomeric silsesquioxanes (POSS) are used to impart potential flame-retarded properties to polymers. In this work, polystyrene nanocomposites containing octa(tetramethylammonium) POSS and organic clay were prepared by melt mixing method, and their enhanced combustion and thermal properties were investigated and discussed. The microstructures of composites obtained by TEM characterization indicated that POSS and clay were dispersed in the base polymer homogeneously. The thermal and combustion behaviors of composites were investigated by thermal gravimetric (TG) analysis and cone calorimeter. TG results obtained under air atmosphere show that the char yield increases obviously. Heat release rate together with other combustion parameters (such as the release rates of CO and CO2, the concentration of CO and CO2 and the smoke production rate) of composites is enhanced effectively. More importantly, the results show that 5 % replacement of POSS by organic clay is very helpful to the further improvements in most of parameters and cut down the cost effectively. Of course, nanoscopic size and structure of POSS and clay together with their well dispersion contribute to these improved fire safety properties.