ABSTRACT
Organosilicone adjuvants have been used as defoamers, this chapter focuses on the use of organosilicone surfactants as activator adjuvants: that is, adjuvants that enhance the activity of the active ingredient in the spray solution. Organosilicone adjuvants have also been used with the foliar application of organic and inorganic fungicides, insecticides, nutrients, and growth regulators. Organosilicone surfactants of the foregoing structure are in commercial use as agricultural adjuvants. These surfactants are also used in adjuvant blends in combination with organic surfactants and/or vegetable oils. The ability of organosilicone surfactants to dramatically reduce the surface tension of water leads to rapid spreading on hydrophobic surfaces. Water droplets or agrichemical spray solutions containing organosilicone surfactants spread completely over leaf surfaces in a matter of seconds, and the droplet contact angle is zero. For cost reasons, organosilicone surfactants are often blended with organic nonionic surfactants. When used in concentrations sufficient to produce rapid spreading, organosilicone surfactants enhance the activity of fungicides and insecticides.
