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"°`56""5' Prog ress in Colloi d & Polymer Science Fortschrittsberichte i ber Kolloide und Polymere Supplements to "Colloid and Polymer Science" Journal of the Kolloid-Gesellschaft • Continuation of Kolloid-Beihefte • Official • Editors : F . HORST MOLLER-Marburg and ARMIN WEI SS-Mi nchen INTERFACE CHEMISTRY Lectures of the 5th Northern European Symposium on Interface Chemistry Ábo (Finniand) 1973 With 36 figures and 11 tables Dr. Dietrich Steinkopff Verlag- D-6100Darmstadt • P.O. Box 1008 CONTENTS • INHALT 1. Fitch, R. M. and Lih-bin Shih (Connecticut/USA), Emulsion Polymerization: Kinetics of radial capture by the particles (With 8 figures and 5 tables) . . . . . . . . 1 2. Forslind, E. (Stockholm/Sweden), Liquid Water at Interfaces (With 2 figures and 2 tables) 12 3. Friberg, S. and I. Lapczynska (Stockholm/Sweden), Microemulsions and solubilization by nonionic surfactants (With 6 figures) . . . . . . . . . . . . . . . . 16 4. Stenius, P. and L. A. Fil~n (Abo/Finland), The influence of solubilized N-Decanol on the stability of sodium N-Pentanoate (sodium valerate) micelles (With 6 figures and 3 tables) 21 5. Svens, B. and M. Turpeinen (Abo/Finland), Investigation of isotropic micellar solutions in the system sodium octaanoate - N-Alcohol - water by small-angle X-Ray scattering With 5 figures and 1 table) . . . . . . . . . . . . . . . . . . . . 30 . Lincoln, Britta (Stockholm/Sweden), The Solubilization of Water in Polyoxyethylene Alkyl Ethers and the Influence on the Bonds between the Ethers and Fatty Acids (With 9 figures) . . . . . . . . . . . . . . . . . . . . . . . . . . 37 PROGRESS IN COLLOID AND POLYMER SCIENCE Supplements to "'Colloid and Polymer Science" " Continuation o] ,,KoUoid-Beihe]te'" Vol. 56 1975 1 Department of Chemistry and Institute of Materials Science, University of Connecticut Storm, Conn. 06268 (U. S. A . ) Emulsion polymerization: Kinetics of radical capture by the particles R. M. Fitch and L i h - b i n S h i h With 8 figures and 5 tables (Received January 17, 1974) Introduction The rate at which free radicals enter particles of the disperse phase from the continuous phase in emulsion polymerization depends upon the particle concentration and size and the rate of radical generation. The kinetics of radical capture determine the rate of particle formation, relative growth rates of different sized particles in certain cases and the chemistry of the polymer/water interface. Smith and Ewart in their classic work (1, 2) assumed, on the basis of a suggestion by P. Debye, that the process of radical capture by particles was diffusion-controlled to calculate the particle number concentration and one part of their "Case 1" polymerization kinetics. Under diffusion control, the radical absorption rate is proportional to the radius of the particlea. There is good evidence to support this model: Ugelstad and coworkers applied it to calculate relative particle growth rates (3) and overall kinetics of vinyl chloride emulsion polymerization (4), and La Mer and Reiss found that the growth of aerosols and hydrosols could be ascribed to diffusion-controlled absorption of small molecules by particles (5, 6). On the other hand Gardon proposed.that the capture of radicals by monomer-swollen soap micelles should be described by a collision theory which gives a dependence of the capture rate on the square of the particle radius (7). Fitch and Tsai applied this theory to calculate particle nucleation kinetics (8). Alexander and Napper in an excellent review have recently stated that whether radical entry is diffusion- or collision-controlled is still an M 934 open, important question which needs to be res