Prediction of vinyl chloride drop sizes in stabilised liquid-liquid agitated dispersion

Drop sizes and drop size distributions have been determined for stabilised dispersions of vinyl chloride (VCM) in agitated aqueous solutions of hydrolysed poly(vinyl acetate). For this system, where drop sizes depend on breakage (rather than on coalescence), experimental measurements confirm the assumptions that the Sauter mean drop diameter is proportional to the maximum drop diameter. Increases in volume fraction of the dispersed phase lead to widening of the drop size distribution. When the agitator speed is reduced, the size distribution changes from monomodal to multimodal. By using estimates of interfacial tension and dispersion density, a complete relationship between drop size, volume fraction of VCM and Weber number is obtained.

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