Diameter, average particle latex samples

Table IV. Diameter Averages for Latex Particles Measiired at 280 nm For each sample.

Particle-Size Determination Particle-size of the cleaned1 latexes were determined using transmission electron microscopy after freeze-drying the samples and counting the particles with a Quantimet image analyzer. The number average particle diameters ( n) of the homopolymer, the 85/15 VA/BA and 70/30 VA/BA latexes were found to be 0.Q57/ m, 0.062/<.m and 0.073 m, respectively. 

From the observed values of the particle size analysis of each of the latex samples, the number and weight average diameters of the particles, the size distributions, and the standard deviations, S.D., of the average diameters were calculated. Knowing the rate of polymerization and the total number of particles in a system, the rate of polymerization per particle, Rpp, can also be calculated. The values are listed on Table III, where it can be seen that, in comparison with the other two recipes, the one with surfactant ratio of r = 0.207 has the following features. 

Polystyrene latices used as an adsorbent were prepared by the Kotera-Furusawa-Takeda method(8 to reduce the spurious effects of surface active substances. The average diameter(D) and the surface gharge density(ao) of the latex particles were determined D=2000 A and 0O = 1.5 uC/cm. A silica sample was prepared by the method described by Stttber et al.(9), and was composed of highly mono-disperse spherical particles of 1900 X in diameter. These colloids were used after dialyzing exhaustively against distilled water to remove the ionic impurities. 

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