Product Name: Sodium Dibutyl Naphthalene Sulfonate (Commonly known in the industry as Penetrant BX or SDNS)
CAS Number: 130-39-2 / 25638-17-9
Chemical Formula: C₁₈H₂₈NaO₃S
Primary Applications: Agricultural agrochemical dispersant, textile wetting agent, leather tanning auxiliary, and heavy-duty industrial emulsifier.
1. Product Overview
Sodium Dibutyl Naphthalene Sulfonate (SDNS) is a highly robust, multifunctional anionic surfactant. It is engineered by sulfonating a naphthalene ring and attaching two hydrophobic butyl chains, followed by sodium neutralization.
This specific “dibutyl” modification drastically increases its amphiphilic properties compared to standard naphthalene sulfonates. The dual butyl tails aggressively seek out and bond to non-polar substances (like oils, greases, or water-repelling plant waxes), while the polar sulfonate head remains locked into the water phase. The result is a chemical that dramatically crashes surface tension, acting simultaneously as a high-speed penetrant, a stable emulsifier, and an anti-clumping dispersant.
2. Physical & Chemical Specifications
(Manufactured to Green Agrochem’s premium industrial standards. Available in both a dry powder and a liquid concentrate.)
| Parameter | Specification (Powder) | Specification (Liquid) |
| Appearance | Beige to Light Yellow Powder | Light Yellow to Amber Liquid |
| pH Value (1% aqueous solution) | 7.0 – 9.0 | 7.0 – 9.0 |
| Active Matter Content | ≥ 70.0% | 17.0% – 20.0% |
| Density (at 25°C) | 0.40 – 0.60 g/cm³ (Bulk) | 1.07 – 1.12 g/cm³ |
| Solubility | Easily soluble in water/organics | Fully miscible |
| Foaming Profile | Moderate to Low Foam | Moderate to Low Foam |
| Thermal Stability | Stable in aqueous solutions up to 100°C |
3. Key Industrial Benefits
Because it remains entirely stable in extreme environments—including highly acidic baths, harsh alkaline cleaners, and mineral-heavy hard water—SDNS is a staple across multiple manufacturing sectors:
For Agriculture (Agrochemical Dispersant & Wetter):
- Uniform Active Dispersion: When formulating Wettable Powders (WP) or Suspension Concentrates (SC), SDNS coats the raw, insoluble pesticide particles. The negative electrostatic charge forces the particles to repel one another, completely preventing sludge or sediment buildup in the spray tank.
- Leaf Cuticle Penetration: Plant leaves naturally repel water. SDNS breaks that surface tension immediately, allowing the herbicide or fungicide to spread flat across the waxy leaf and penetrate the plant tissue before it can evaporate.
For Textiles & Leather:
- Flash Wetting: In textile pre-treatment (dyeing and bleaching), SDNS forces the treatment fluids deep into the core of the raw fiber, ensuring uniform, level color uptake without causing the extreme foaming issues associated with other surfactants.
- Leather “Syntan” Agent: Acts as a synthetic tanning agent. By cross-linking with collagen fibers in raw hides, it enhances dye penetration and gives the finished leather a noticeably plump, soft, and full-bodied feel.
For Industrial Cleaners & Emulsion Polymerization:
- Heavy-Duty Degreasing: The dibutyl groups make SDNS an exceptionally aggressive emulsifier for removing stubborn machine oils, metalworking fluids, and automotive greases in industrial wash-downs.
- Rubber & Paint Stability: During the production of synthetic rubber (like SBR) or water-based latex paints, it stabilizes the emulsion, ensuring the microscopic oil droplets do not recombine and separate out of the mixture.
4. Recommended Dosage & Formulation Notes
SDNS is highly compatible with other anionic and non-ionic surfactants, allowing for synergistic blends in complex chemical formulations.
- Agrochemical Powders: Typically blended at 2.0% to 5.0% by weight into dry pesticide formulations to ensure rapid wet-out and long-term suspension stability.
- Textile Dye Baths: Add 1.0 to 3.0 g/L to the dye vat. Its electrolyte tolerance means it will not precipitate out, even if you are using high concentrations of sodium chloride to drive the dye into the fabric.
- Industrial Cleaners: Commonly makes up 3.0% to 10.0% of heavy-duty liquid degreasing formulas, depending on the severity of the soils being targeted.
5. Packaging & Storage
- Powder Packaging: Supplied in standard 20 kg / 25 kg woven poly bags with a moisture-blocking inner liner.
- Liquid Packaging: Shipped in high-density 200 kg plastic drums or 1000 kg IBC Totes.
- Storage Protocol: Store indoors in a cool, well-ventilated space. The powder formulation is moderately hygroscopic; ensure open bags are tightly sealed to prevent moisture absorption and caking.