| 초록 |
Poly(ethylene terephthalate) (PET)/polyhedral oligomeric silsesquioxane (POSS) nanohybrids were prepared by the melt mixing, where POSS was functionalized with octamethyl-, octaisobutyl- and octaphenyl groups. Thermal, mechanical and dynamic mechanical measurements using TGA, UTM and DMA revealed that the functional group and the concentration of POSS played important roles in defining structure-property relationships. Thermal characterization revealed that the incorporation of octaisobutyl-POSS induced a slight increase in the decomposition temperature compared with unfilled PET. However, the decomposition temperatures of PET/ octamethyl- and octaphenyl-POSS nanohybrids were found to decrease. Also, we found the glass transition temperatures of nanohybrids did not increase in dynamic mechanical measurement. It is believed that the bulkiness of the POSS group created free volume and chain separation, leading to a reduction in the glass transition temperature. |
