Spectroscopy as a Tool for Characterization of Monomer Emulsions

Abstract

The properties of the emulsions can be described by the droplet size distribution, which gives a statistical inventory of the dispersed phase fragmentation. This research reports measurements of droplet size distribution from multiwavelength transmission data and estimated of droplet size from electron microscope/osmium tetroxide technique. The quantitative interpretation of the transmission spectrum is performed in the spectral range (300–820 nm) leading to reliable estimated of droplet size populations in the range of 1–20 µm as function of the monomer concentration. The measurements reported are fast, highly reproducible and potential applicable to emulsification and polymerization processes.

Abbreviations: Au absorbance units; UV‐vis ultraviolet‐visible; CMC, critical micellar concentration; C_m, monomer concentration calculated from dilution process; De, monomer concentration corresponding to electron microscope measurements; x¯, mean of the sample; s, standard deviation of the sample; DSD, droplet size distribution; PSD, particle size distribution.

Keywords:

• Emulsion
• droplet size
• multiwavelength spectroscopy
• particle characterization
• emulsion polymerization

Acknowledgments

The authors thank to the Venezuelan National Research Fund (FONACIT‐Grant N° F‐2005000175, Imperial Chemical Industries (ICI) and to the University of the Andes Research Council (CDCHT‐ Grant N° I‐817‐05‐08 B) for sponsoring the research program at the POLYCOL (Polymers and Colloids) laboratory.

Notes

Abbreviations: Au absorbance units; UV‐vis ultraviolet‐visible; CMC, critical micellar concentration; C_m, monomer concentration calculated from dilution process; De, monomer concentration corresponding to electron microscope measurements; x¯, mean of the sample; s, standard deviation of the sample; DSD, droplet size distribution; PSD, particle size distribution.