Overview of nanocomposite structure and crystallization behavior

The purpose of this study is, first, to investigate the structure of the PVA/MMT nanocomposites, with the focus on the layered filler dispersion, as well as on the changes of the polymer ciystallinity due to the inorganic layered fillers. 

Subsequently, through the study of selected nanocomposite material properties, we attempt to correlate the hybrid structure with changes in the material response. The structure is explored over the full range of silicate compositions. On the other hand, properties are explored only for the low silicate loadings, which are relevant to potential applications. 

The model water soluble polymer/silicate nanocomposite systems presented here also possess unique thermal properties which can be studied using various techniques. These include DSC and thermal gravimetric analysis. Thermal properties for the PVA/silicate system are outlined in the following sections. 

Bulk PVA has a glass transition at Tg = 70°C and a melting transition at Tm = 225°C. For fully intercalated PVA hybrids (i.e. all the polymer is intercalated in MMT galleries) DSC does not detect any traces of thermal transitions between 35°C and 250°C (Fig. 8.14), hybrids with 60wt.%). For these neatly intercalated nanocomposites, both the Tg and are either too 

A systematic study of the DSC traces with mmt (Fig- 8.14) shows that the Tg and Tm signals weaken gradually, and disappear for / mmt above 60wt.%. This 

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