Particle Break-Up and Exfoliation

For the polymerization to continue, monomer must be absorbed onto the surface of this polymer layer and diffuse through it until reaching the active sites. After filling up the catalyst support pores, the hydrodynamic pressure caused by the growing polymer breaks the support into many fragments that are known as micrograins, microparticles, or primary particles. 

Extensive fragmentation and uniform particle growth are key indications that the replication process is proceeding as desired. Good replication requires the high support surface area, homogeneous distribution of active centers throughout the particle, and free access of the monomer to the innermost zones of the particle. 

Maneshi et al. [61] developed and used the MLM to investigate clay-supported polymerizations from a theoretical point of view and concluded that, when the active sites were uniformly distributed on the day surface, a uniform monomer 

A review of methods for the detailed characterization of polymer-clay nanocomposites is beyond the scope of this chapter. Valuable information on this area can be found in several literature reviews [13, 46, 63-68]. 

This concept is useful for the interpretation of particle break-up during in-situ polymerization with clay-supported catalysts. Maneshi et al. [69] used ethylene 

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