| Abstract: | An approach to prepare high solids content latexes (> 50 wt %) is presented. The approach is based on a two-stage polymerization where in the first stage low-to-medium solids content seed latexes with a broad particle-size distribution (PSD) were prepared by semicontinuous miniemulsion polymerization. In the second polymerization stage, the solids contents of the latexes prepared in the previous step were increased to 60–70 wt % using relatively low emulsifier concentrations. The approach was used successfully to prepare fluid- and coagulum-free poly(n-butyl acrylate) latexes up to solids contents of 61 wt % using an emulsifier (sodium lauryl sulfate) concentration of 0.5 wt % based on a monomer. Nonfluid (pastelike) latexes having solids contents higher than 61 wt % were also prepared using this method. As a result, some guidelines related to the required particle-size distribution to produce fluid latexes of higher solids contents are also presented. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1797–1809, 1997 |
