SL additives
Soluble Concentrates (SL)
In SL formulations active ingredient contents between 10 – 50 % can generally be realized.
The pesticide is dissolved in water or a water-soluble organic solvent. To enhance the efficiency and efficacy of the spray mixture, penetration enhancers and wetting agents are often included. Also, water-insoluble co-formulants might be added, for example, anti-foam agents.
For a long-term stable formulation the pesticide must be resistant to hydrolysis. Especially when ionic actives are formulated, a high level of foam might be formed.
Key-factors:
- Pesticide must be soluble and stable in water (or polar solvent)
- No crystals must form upon storage
General recipe
| SL ingredients | w/v% |
|---|---|
| Active ingredient | 10-50 |
| Penetration or wetting adjuvants | 5-25 |
| Stabilizer (pH, buffer, anti flocculation agents) | 0-20 |
| Water or a water soluble solvent | to 100 |
Products
Built in solution
| Trade name | Chemistry | Property | EPA |
|---|---|---|---|
| LUCRAMUL® AG 4802 | Aqueous surfactant blend (TFA free) | Compatible with glyphosate/glufosinate | |
| LUCRAMUL® AG 4820 | Aqueous surfactant blend (TFA free) | Compatible with glyphosate/glufosinate | |
| LUCRAMUL® LOFO 1 | Low foaming aqueous surfactant blend (TFA free) | Compatible with glyphosate/glufosinate | |
| LUCRAMUL® LOFO 2 | Low foaming aqueous surfactant blend (TFA free) | Compatible with glyphosate/glufosinate |
EPA can be submitted on request
Conventional vs. Low-Foaming Surfactant Blends
Finding the best surfactants for generating efficient formulations can be difficult. Here we introduce four built-in additives for soluble concentrate (SL) formulations showing excellent results as wetting agents. Two of them (LUCRAMUL® LOFO 1 and LUCRAMUL® LOFO 2) are designed for low foam formation.
Surface tension and foam persistency was tested with spray mixtures containing 1% of the following glufosinate ammonium SL formulations:
| a.i. (glufosinate ammonium) |
Surfactant (LUCRAMUL®) |
|||
| No. | [g/l] | LUCRAMUL® | [g/l] | |
| Conventional surfactants | 1 | 200 | AG 4820* | 280 |
| 2 | 200 | AG 4802** | 250 | |
| 3 | 400 | AG 4802** | 250 | |
| Low foam surfactants | 4 | 400 | LOFO 1** | 250 |
| 5 | 200 | LOFO 2** | 250 | |
| 6 | 400 | LOFO 2** | 250 | |
* sodium laurylether sulfate (SLES) based
** alkyl poly glycoside (APG) based
The LUCRAMUL® AG types and the LUCRAMUL® LOFO types have a sufficient strength in lowering the dynamic surface tension:
The dynamic surface tension profiles of LUCRAMUL® AG types indicate good wetting properties, whereas a lower foam formation was observed with the LUCRAMUL® LOFO types. LUCRAMUL® LOFO 1 shows remarkably good properties in both measurements producing the lowest amount of foam and the best dynamic surface tension.
The foam volume of the formulations 4-6 containing LUCRAMUL® LOFO 1 or LOFO 2 directly after mixing is significantly lower compared to formulation 1-3 using conventional surfactants. After 30 minutes the foam volume is decreased even further.
LOFO 1 is best used for highly concentrated formulations (>35% active). For low active content LOFO 2 forms stable and efficient formulations.