Granular Carrier Effects on Volatility of Pesticide Formulations
SourceVolatile organic compounds (VOCs) have been increasingly important in all formulation areas, including pesticides. In recent years, ASTM Method E2686-09 was developed to determine VOC content in formulations using granules to mimic soil types. The granules chosen are often used as agricultural chemical carriers. Volatility differences were noted. This paper used ASTM method E2686-09 as a model and examined different granular carriers. Inorganic, organic, and combination inorganic/organic carriers were investigated. Several types of formulation solvents were used. Volatility depended on granule type and solvent. In addition, a correlation was found between the types and amounts of pores (macropores, mesopores, and micropores) in the different carriers, and how well those carriers were able to retain the VOCs. In general, inorganic clay granules that contained mesopores and micropores showed less volatility than either organic or combination inorganic/organic carriers, which all lacked mesopores and micropores.