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Physicochemical Properties of Adjuvants: Values and Applications

Published online by Cambridge University Press:  20 January 2017

David Stock  and
Geoff Briggs
Geoff Briggs
Affiliation:
Aventis CropScience, Centre de Recherches de La Dargoire, 69009 Lyon, France
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Abstract

The physicochemical properties of adjuvants determine their function and impact upon biological activity. Various physicochemical parameters are key to modifying both the preretention events and postretention consequences of adjuvant usage, irrespective of whether the adjuvants are tank-mix additives or built into a formulation. This paper discusses several key adjuvant parameters for a range of adjuvant chemistries alone and in mixtures. In addition, the misleading use of terms such as nonionic surfactant and hydrophile–lipophile balance is addressed. From a more coherent understanding of the parameters involved, it can be shown that there are ways of predicting the required properties of an adjuvant to solve specific delivery problems. The recognition that different problems often require quite different approaches illustrates that good adjuvants do not exist per se, only materials that should be rationally selected for specific reasons. The chemistry of the herbicide and the nature of its targets will dictate adjuvant selection criteria.

Keywords

a.i., active ingredientBO, butylene oxideDUE, deposit per unit emissionEC, emulsifiable concentrateEH, equivalent hydrocarbonEO, ethylene oxideEW, concentrated emulsifierHLB, hydrophile–lipophile balanceLLP, light liquid paraffinNIS, nonionic surfactantNP, nonylphenolPEG, polyethylene glycolPO, propylene oxidePVA, polyvinyl alcohol
Type
Symposium
Information
Weed Technology , Volume 14 , Issue 4 , December 2000 , pp. 798 - 806
Copyright
Copyright © Weed Science Society of America 

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References

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