Propagation in Competition with Condensation

It is sometimes the case in cationic polymerization that growth of macromolecules occurs not only by the monomer addition to polymer chain, but also by condensation 

This kind of mechanism is observed in cationic polymerization of cyclosiloxanes  

It was shown that in the polymerization of hexamethylcyclotrisiloxane in the presence of CF3SO3H the monomer ist mostly consumed by the addition. However, the condensation has strong impact on the kinetics of this process °  

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