Adjuvants An overview of the adjuvants in use in Region 8

Adjuvants Any material added to a pesticide mixture to modify its behavior; includes wetting agents, spreader stickers, other surfactants, penetrants, and drift control agents

Adjuvants – some definitions Polar vs. non-polar Polar compounds are compounds which have, due to their structure, have a definite imbalance in charge – resulting in a positive and a negatively charged end - + Polar bear?

Adjuvants – some definitions Polar vs. non-polar Non-polar compounds are compounds which have evenly distributed charge throughout their molecules

Adjuvants – some definitions R + - PolarNon-polar

Adjuvants – some definitions Polar vs. non-polar Polarity in a chemical aids in spreading the chemical over a polar surface or in penetrating one

Adjuvants – some definitions Ionic vs. non-ionic In solution ionic molecules separate into positively and negatively charged subparts (ions) while non-ionic molecules do not

Adjuvants – some definitions Ionic vs. non-ionic R + - Ions from an ionic compound Non-ionic molecule

Adjuvants – some definitions Ionic vs. non-ionic Ions from an ionic compound can interfere with the activity of a polar or an ionic pesticide while non-ionic compounds do not

Adjuvants

Surfactant Any material added to a pesticide formulation which is designed to modify the surface characteristics of the target organism

Surfactants

Wetting Agent Any material added to a pesticide mixture which serves to make the surface “wetter” so as to allow more rapid spread of the pesticide on the target – often called a ‘spreader’ Without wetting agent With a wetting agent

Wetting agents

Penetrant Any material which modifies the target surface in a way which allows more rapid penetration of the surface of the organism by the pesticidal formulation

Penetrants Mineral oil Napthenic oil Diesel oil

Penetrants Vegetable oil Organic silicone

Penetrants Products designed to create invert emulsions (oil in water)

Spreader Any material added to a pesticide formulation which improves the formulations ability to rapidly form a film on the target surface – generally interchanged with “wetting agent”

Sticker Any material added to a formulated pesticide which improves the ability of the pesticide to adhere to the target surface

Stickers

Drift Control Agent Materials added to a mixture to increase the size of droplets and decrease the tendency of the pesticide to drift off- target

Drift control agents

Materials added to a formulation which marks a treated stem so that later identification of those treated vs. not treated is simplified Dyes in either amine or ester formulations are the most common pattern indicators

Pattern indicators