Clay as a Polymerization Additive

In this method, the organoclay, the catalyst precursor, and the activator (alkylalu-minum compounds or alkylaluminoxanes) are added to the reactor and the polymerization is started by introduction of the olefin monomer. This is the simplest in-situ polymerization method, and only few reports [1, 51, 70, 71] have been published investigating this method for production of polyolefin-clay nanocomposites. In comparison to the other in-situ polymerization methods, this method seems to have the lowest polymerization activities, although it is often difficult to compare catalysts activities for polymerizations done at very different conditions and following distinct procedures. 

For polymerizations in the presence of MAO-modified clays, especially if additional MAO is added to the reactor, a considerable fraction of the active sites may be extracted from the support and become active in the solution. In this case, 

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