Polymer latices, particle size distribution analysis

Recently, a miniaturized thermal apparatus, [t-ThFFF, was developed and applied to characterize the molar mass distribution of synthetic polymers in organic solvent as well to determine the particle size distribution of nanoparticles (PSs latex) in aqueous carrier. This 4-ThFFF proved to performed well in both macromolecule and particle analysis [48]. 

In the earlier publications (1,2) it was shown how hydrodynamic chromatography (HDC) could be applied in the study of polymer latexes to determine particle-size. An improved technique for the HDC was developed which utilized higher efficiency and resolving power columns to significantly reduce the analysis time (3). A high speed integrated computer was included in this improvement so that both particle-size and particle-size distribution of latexes could be quantified in the relatively short period of time. This high speed computerized version of the HDC has been used extensively for measurements on the final latex. 

J. A. Davidson, E. A. Collins, H. S. Haller, Latex Particle Size Analysis, Part 3 Particle Size Distribution by Low Ultra Microscopy ,/. Polymer Sci., Part C 34 (1971) 235-255. Commercial information is available from Prototron, Inc., 1020 Corporation Way, Palo Alto. California 94303. 

For the development, production, and application of polymer latices the determination of the size distribution and the analysis of the chemical composition and heterogeneity of the latex particles are important. The size distribution can be determined rapidly by ultracentrifugation, electron microscopy or light scattering > but for the analysis of the... 

The potential of SAXS for a precise analysis of the radial structure of latexes can be discussed best when considering model particles consisting of a well-defined core and a closed shell of a second polymer. The particles analyzed by SAXS [45-49] have been prepared recently [45] by a seeded emulsion polymerization [97] of PMMA onto a polystyrene core having a narrow size distribution. The alteration effected by seeded emulsion polymerization can be seen directly in the analysis of the size distribution by ultracentrifugation [87], the resulting distributions are shown in Fig. 17. Besides the increase in radius when going from the... 

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