In-situ Stereospecific Polymerization

Trying to summarize our experience about the in-situ synthesis of PB/day nanocomposites, we can say that this technology involves the following three main steps  

1) designing of organoclay by interlayer and edge-surface hydroxyls modification  

2) synthesis of a clay-supported catalyst by successive intercalation of an aluminum alkyl cocatalyst (e.g., methylaluminoxane (MAO)) and a transihon metal complex  

3) in-situ polymerization by using the clay-intercalated catalyst in a solvent-monomer mixture. 

In view of these findings, it is easy to imagine how the key stage of this in-situ approach is the immobilization of the aluminoxane cocatalyst within the clay carrier sheets. Therefore, a full complement of structural X-ray investigation and TEM analysis of the clay-MAO intermediate before the polymerization becomes crucial to have a right check of the filler intercalation extent in the polymer matrix. 

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