| 초록 |
In this study, to quantify the interface and surface effect on polymer nanocomposites, the inorganic filler effect on the glass transition temperature(Tg) of composites was investigated. PMMA nanocomposites were prepared by the addition of silica filler as a function of silica volume. The Tg of poly(methyl methacrylate)(PMMA)/silica and polystyrene(PS)/silica were investigated in the bulk with differential scanning calorimetry(DSC). At lower silica volume, the Tg of the PMMA/silica composite was increased by 5o°C, when compared to the PMMA bulk Tg. But the Tg of the PS/silica composite did not decreased, when compared to the PS bulk Tg. The increase of the Tg of PMMA composite is dependent on strong interactions between PMMA and silica. The Tg of PS/silica nanocomposites is not. To explain the Tg variation, we modified the equation of the thickness-dependent Tg on thin polymer film. The variation of the Tg of polymer composites was explained by silica radius and volume fraction. |
