Four centred collision

Aspects of the sono-chemical degradation mechanism After the establish of the ultrasound waves physical and chemical components, the mechanisms of sono-chemical destruction have dominantly been interpreted on this basis. Thus, in the cavitation bubble collapse moment, N.Sata and H. Okuyama defined four types of possible reactions, namely 1) collision of the polymer - polymer molecules, occurring by a bimolecular reaction 2) collision of the polymer-solvent molecules, which proceeds by a pseudo-monomolecular reaction 3) intramolecular collision that occurs by a monomolecular reaction and 4) tearing resulting from the entanglement points that gives a monomolecular reaction. The authors accepted that the active centres of this type of reaction are free radicals and that about 30% from the efficiency of this process is assured by the subsequent reactions of the formed macroradicals with the polymer chains [1130, 1139]. 

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