STP943: Use of Gelling Clays to Stabilize Agricultural Pesticide Suspensions and Emulsions in Aqueous Systems

    Sawyer, EW
    Manager of clay research, Floridin Co., Berkeley Springs, WV

    Pages: 10    Published: Jan 1987


    Abstract

    Pesticides are often supplied as suspension or emulsion concentrates in water systems and even more often are applied in aqueous media at desired field concentrations (tank mixes) to obtain uniform spreads at desired rates. The key to success in these applications is “uniformity,” so that after deposition, pesticides exhibit uniform activity throughout the treatment areas. A well-proven technique for obtaining uniformity in concentrates and field strength blends is that of stabilizing with gelling clays. In this presentation, methods of incorporating the clays into the suspensions and emulsions are discussed. Correlations are made between incorporation techniques, processing equipment available, and the optimum stabilities achievable. Rheological characteristics desired in stable suspensions and emulsions are described and compared with those resulting from clay incorporation. The clay gel structure and the resultant gel strengths and viscosities from the clay crystals plus other contributing particulate materials in the continuous phase gels are discussed.

    Keywords:

    stabilization, pesticides, fertilizers, suspensions, emulsions, gel strength, rheology, agriculture, aqueous systems, clay minerals


    Paper ID: STP19407S

    Committee/Subcommittee: E35.13

    DOI: 10.1520/STP19407S


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