Particle Nucleation and the Role of Surfactant

Particle Nucleation and the Role of the Surfactant.—A recent paper by Hansen and Ugelstad is the first of a series which will deal comprehensively with the theory of particle nucleation in emulsion polymerization. The aim of the series is to discuss in detail the different parameters which affect particle formation, including the nature of the monomer, the capture efficiency of oligomers by particles of different size and nature, the effect of surfactant, and the electrostatic repulsion caused by charges on the surface of the particles. This first paper is concerned with the behaviour of monomers having relatively low water solubility, and with the case where either the system is surfactant-free, or, if 

Garden, Mechanism of Emulsion Polymerization , in Applied Polymer Science , ed. J. K. Craven and R. W. Tess, Organic Coatings and Plastic Chemistry Division, American Chemical Society, Washington D.C., 1975, p. 138. 

Eliseeva, S. S. Ivanchev, S. I. Kuchanev, and A. V. Lebedev, Emul sionnaya Poli-merizatsiya i ee Primenenie v Promyshlennosti , Khimiya, Moscow, U.S.S.R., 1976, 

Interest continues to be shown in the use of surfactant HLB values for predicting behaviour in emulsion polymerization tems. Askarov and Trubitsyna have studied the kinetics of the emulsion polymerization of methyl methacrylate in the presence of polymeric surfactants. They find that both the rates of polymerization and the molecular weights of the products are Iowa than those obtained using conventional surfactants. They interpret these observations in terms of less efficient particle nucleation when polymeric surfactant is used. 

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