High solids polymer dispersions

Combining process and property models: Development of novel reaction strategies for high‐solids, low‐viscosity latices

“…A general trend can be found in polymerization procedures dealing with high‐solids latices that constitutes, either implicitly or explicitly, ways of producing a polymer dispersion having a broad particle size distribution (PSD), usually depicted as the sum of a PSD of large particles with a PSD of small particles 2–9, 12–27. For ease of comparison, techniques may be grouped according to the means used to manipulate the PSD, and by the mode of operation, either batch12, 18 or semibatch 2–9. Within the semibatch group several subgroups are found.…”

“…Under similar conditions, conventional emulsion polymerization could not lead to stable systems beyond 50% solids content. Becker et al18 used a blend of rather large (>1 μm) and small particles, where particles were swollen with monomer and further polymerized. The authors remarked that, for the production of high‐solids latices, one needs: first, a basic understanding of the main factors influencing the viscosity; second, the expertise for the creation of a desired PSD for a given monomer and stabilizer system; finally, the resulting product should possess required defined application properties.…”

Latex Particles

“…To get latexes with solids content about 70% or even higher requires polymodal particle size distributions with larger and smaller spheres (the smaller sphere have to fit in the interstices between the larger ones). This principle was successfully applied to get high solids polymer latexes up to 70% solids content and low viscosity [120]. It was found that there is a critical ratio between the larger and smaller sphere diameters, which should be above 10 in order to get both low viscosities and high solids content.…”

“…It was found that there is a critical ratio between the larger and smaller sphere diameters, which should be above 10 in order to get both low viscosities and high solids content. The preparation of polymodal latexes requires the occurrence of multiple nucleation events in the course of the polymerization, which can be realized either by emulsifier feeding protocols [121,122] and/or by proper choice of recipe components (co-monomers) [120].…”

Development of a Coupled Viscosity‐Polymerization Model for the Synthesis of High Solids‐Low Viscosity Latexes

“…Techniques can be grouped according to the means employed to manipulate the PSD and by the mode of operation, either batch or semi‐batchwise. Batch polymerization examples are restricted to miniemulsion4 and seeded polymerizations 5. The miniemulsion strategy tries to take advantage of the longer nucleation period characteristic of some miniemulsions to produce a very broad PSD.…”