A Study of Morphology and Intercalation Kinetics of Polystyrene−Organoclay Nanocomposites
作者
Yuqin Li,Hatsuo Ishida
出处
期刊:Macromolecules [American Chemical Society] 日期:2005-06-28卷期号:38 (15): 6513-6519被引量:78
标识
DOI:10.1021/ma0507084
摘要
Temperature-modulated differential scanning calorimetry (TMDSC) is used to study the heat capacity ( C p ) of monodisperse polystyrene in the nanocomposites. It is found that the bulk portion of polystyrene in the nanocomposites has a similar temperature range of glass transition behavior as pure polystyrene, while the normalized Δ C p of polystyrene in the nanocomposites strongly depends on the polystyrene concentration. Results from TMDSC, especially the combination of kinetic study of TMDSC and X-ray diffraction, indicate that intercalated polystyrene does not contribute to the Δ C p and does not have glass transition at the regular glass transition temperature. The maximum amount of intercalated polystyrene is around 40 wt %, and this amount will not increase as polystyrene concentration increases as long as the polystyrene with the same molecular weight is used. On the other hand, the amount of intercalated polystyrene increases when polystyrene molecular weight decreases.