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“Biodiesel is more polar than traditional oils used in OD formulations, which means it requires emulsifiers with higher HLB values to form a stable oil-in-water emulsion upon dilution. The simplest and most effective strategy is to adjust the HLB of the surfactant system to match the required HLB of the oil phase being used.
This adjustment can be done in two ways:

By changing the proportions of the existing surfactants in the formulation to reach the target HLB.
By introducing new surfactants if the current ones cannot achieve the required HLB range.

This approach helps ensure spontaneous emulsification and long-term stability of the formulation, even when working with more polar oils like biodiesel.”

“Fumed silica can be challenging to incorporate, especially in formulations with biodiesel and high solid loads, due to its tendency to agglomerate and its incompatibility with certain anionic surfactants. In our examples, the most effective strategy was to incorporate the fumed silica during the pre-dispersion step, followed by ball milling. This process helped activate the silica, allowing it to form a rheological network within the oil phase, which significantly improved viscosity and stability.
If needed, practical alternatives include:

Pre-dispersing the silica in a compatible oil phase before adding other components.
Using secondary rheological modifiers, such as hydrophobic gums or polymeric thickeners, to support viscosity without compromising safety or stability during manufacturing.

Each approach should be validated through lab testing to ensure compatibility and performance.”

Urea is included in the formulation as a stabilizing agent to prevent degradation of nicosulfuron. It helps protect the active ingredient and maintains its integrity during storage and application, especially in formulations where water or moisture may be present.

The use of DM (demineralized) water in OD formulations can be considered, but it must be carefully evaluated. Adding water in significant amounts can increase the risk of phase separation, since water must be properly emulsified into the oil-based system. If the active ingredient is water-soluble, it may crystallize over time. If it’s sensitive to hydrolysis, water can accelerate its degradation. Therefore DM water inclusion should be justified and tested to avoid compromising the formulation’s stability and performance.

“Some OD formulations become more viscous over time due to the late formation of structural networks between dispersed particles. This happens when dispersants have multiple anchor chains that start connecting across particles, forming a 3D structure that thickens the system.

This is more common in more concentrated systems or when dispersants and emulsifiers overlap in function, causing competition at the interface and rheological instability. Poorly adjusted rheology modifiers can also interact with surfactants and worsen the effect.

To avoid this, simplify the formulation by removing non-essential components. Choosing dispersants with fewer anchor chains helps maintain fluidity. Also, selecting an oil phase with better rheological properties can improve stability and ease of application. “

“A good starting point is to define the emulsifier system before the non-aqueous dispersant. As shown in Indovinya’s studies, this sequence prevents the emulsifier from disrupting the dispersion structure. This is key because emulsifiers can also act as co-dispersants, directly affecting formulation stability.
If the dispersion is already stable and the goal is just to improve emulsification during dilution, the best approach is to fine-tune the HLB using the surfactants already in the formulation. Adding new components at this stage can cause surfactant competition and destabilize the system, especially in sensitive formulations.

So, adjusting the hydrophilic-lipophilic balance (HLB) of existing surfactants is ideal. It ensures efficient emulsification in the tank while preserving the oil-phase dispersion, agronomic performance, and physical stability, avoiding rework and extra costs. “

“Yes, we use small-scale equipment like bench-top dispersers with controlled agitation systems that simulate milling behavior. These allow quick preparation of multiple formulations with minimal input and time, making initial screening easier.

At this stage, we run fast tests for sedimentation, visual stability, and basic rheology evaluation to identify dispersants with good dispersion, flow, and oil compatibility. This speeds up development and helps focus on the most promising candidates.

However, this screening doesn’t replace full testing. Selected dispersants should still go through real-scale milling and more robust evaluations for stability, rheology, compatibility, and agronomic performance. “

None of the coformulants presented are currently listed as OMRI Registered. However, some of them may be eligible for use in organic production depending on their composition and intended use. For specific information regarding compliance or certification, please contact our team directly by connecting.chemistry@br.indorama.net

“Yes, at Indovinya we’ve conducted comparative studies between OD (Oil Dispersion) and EC (Emulsifiable Concentrate) formulations, especially in crops like soybean and corn, focusing on multisite and systemic fungicides.

In one of our trials, we tested formulations with dithiocarbamates, triazoles, and strobilurins — actives with different solubility profiles — applied to soybean leaves infected with Phakopsora pachyrhizie. The OD formulation, designed with optimized polymeric dispersants and emulsifiers, showed better active transport through the leaf cuticle compared to the traditional EC. “

Yes

It depends on the type of release mechanism you want to achieve. If the goal is to trigger release upon contact with water (e.g., rain), you may consider increasing ingredients that are hydrophilic, water-soluble, or swellable. These materials can respond to moisture by dissolving or expanding, allowing the release of the encapsulated contents. For more specific recommendations, we suggest contacting our technical support team, who can help tailor the formulation to your application needs.

In our final milling process, the particle size typically reaches a D90 between 3 and 5 microns, and a D50 between 1 and 2 microns. This ensures good dispersion and stability in OD formulations.

Technical micronized” refers to active ingredients that have been finely ground to a specific particle size suitable for formulation purposes. In our examples, the actives were processed using a conventional ball mill. If you plan to use a micronized active in an OD formulation, it’s important that the particle size matches the one typically achieved through conventional milling. This ensures proper dispersion, stability, and performance of the formulation. Differences in particle size can affect viscosity, sedimentation, and even bioavailability.

“To increase the viscosity of MSO (Methylated Seed Oil), you can incorporate thickening agents that are compatible with oil-based systems. Options include hydrophobic-modified natural gums, lipophilic polymers, or high-viscosity coformulants. However, in our examples, fumed silica was the most effective thickener. It provided a significant viscosity increase while maintaining good stability and compatibility with the formulation components.
It’s important to test the impact of any thickener on the overall system, especially regarding flowability, emulsification, and sprayability.”