Emulsion macroscopic kinetics

Even though all chemical reactions take place at the molecular scale, the gigantic number of reacting molecules allows the use of relatively simple expressions (such as the law of mass action) to describe the average kinetics at the macroscopic scale. Thus, the macroscopic kinetics of emulsion polymerization can be described in relatively undemanding terms. 

Very often, the microstructure and the macroscopic states of dispersions are determined by kinetic and thermodynamic considerations. While thermodynamics dictates what the equilibrium state will be, kinetics determine how fast that equilibrium state will be determined. While in thermodynamics the initial and final states must be determined, in kinetics the path and any energy barriers are important. The electrostatic and the electrical double-layer (the two charged portions of an inter cial region) play important roles in food emulsion stability. The Derjaguin-Landau-Verwey-Oveibeek (DLVO) theory of colloidal stability has been used to examine the factors affecting colloidal stability. 

One major component in the decontaminant is the carrier system which has to solubihze the toxic compounds and the active component simultaneously. For this purpose macroscopic emulsions are often used at present [2]. However, these systems are only kinetically stabihzed and due to the resulting limited lifetime they are only temporary applicable. Hence, in recent years several groups were working on the replacement of these carriers by microemulsions [3,4]. 

Since 1980s, the use of a macroscopic emulsion was established for the decontamination of mustard and nerve agents by the German armed forces. This annlsion is composed of 15wt % perchloroethylene (PCE), 76.5 wt % water, 7.5wt % calcium hypochlorite, and 1 wt % emulsifier Marlowet IHF [2]. Although this medium is only a kinetically stable maaoscopic emulsion, it shows the main features, which are also relevant for microemulsions with respect to solubilization of CW agents. 

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