Pesticides, flowable concentrates

Agricultural (Ag) formulations that are commonly diluted and applied by means of spray equipment include water soluble liquids, emulsifiable concentrates, wettable powders, and flowable suspensions. The choice of which formulation to develop normally depends upon the solubility properties of the technical pesticide. Scientists often must also consider manufacturing costs, field efficacy and product toxicity. 

Tpo understand the physical and colloidal chemical aspects of pesticidal formulations research, one must first understand the objectives of the formulations chemist in his work. Simply speaking, the formulations chemist must take the pure organic chemical pesticide and put it in a usable form for field use. These forms include wettable powders, emulsifiable concentrates, dusts, granules, water-soluble concentrates, flowables, and an aerosol, to name a few types of concentrates. The formulations chemist desires to put together a formulation that (1) is easy and eco-... 

The active ingredient (liquid or dry) is incorporated by a special process in small, permeable sph s of a polymer or plastic, 15 to 50 pm (1 pm = 10 m) in diameter. These spheres are then mixed with wetting agents, thickeners, and water to give the desired concentration of pesticide in a flowable form, usually 2 pounds per gallon. After the required dilution, the pesticide spray mixture can be applied with conventional sprayers. The pesticide is released gradually over a period of time. 

If the pesticide constituent is a solid that is not soluble in oil or water, dien either a suspension concentrate (SC) or a water dispersible granule (WG, WDG) can be evaluated. A suspension concentrate is a dispersion of active ingredient in a continuous aqueous phase. The concentrated suspension is then diluted in the spray tank prior to application. If the solid has to be dispersed in an oil phase, then the oil flowable (OD) has to spontaneously enuilsify if it is to be diluted into an aqueous spray tank. 

---