November 18, 2022
The agrochemical industry continues to see growth in aqueous-based formulations, including suspension concentrates (SC) and suspoemulsions (SE). SCs specifically have shown strong growth to become the most valuable formulation type globally after surpassing emulsifiable concentrates (EC) in 20141. Aligned with industry and grower objectives on sustainability, SCs offer many advantages including an improved safety profile, the elimination of costly solvents and the ability to formulate new active ingredients that often have limited solubility in solvent-based formulations.
When developing suspension-based formulations, there are two key technical challenges that must be overcome to achieve good product performance. First, the concentrated formulation must be stable over a wide range of temperatures under prolonged storage. Second, the formulation must dilute homogeneously while also demonstrating stability during the application window. Working against stability are the multiple physicochemical forces that must be overcome, even in formulations with only a single active ingredient (AI). As these systems tend to be thermodynamically unstable, particles will try to stabilize by reducing their surface area via agglomeration, Ostwald ripening or other mechanisms.
The right dispersants can help overcome these challenges, however, as microplastic and additional regulations come into force in the coming years, formulators will need to take further considerations when selecting the appropriate co-formulant for aqueous formulations.