Question

What are the main components of high-concentration fast wetting agent T-75A?

Answer
2026-05-17 官方文档 高含量快速渗透剂T-75A

The main component of high-concentration fast wetting agent T-75A is dioctyl sodium sulfosuccinate (DOSS), with a content of ≥75%

Detailed Description

The core active ingredient of high-concentration fast wetting agent T-75A is dioctyl sodium sulfosuccinate (DOSS), with CAS number 577-11-7. This product belongs to the anionic surfactant category, and its chemical nature is a diester-type sulfosuccinate obtained by esterification of maleic acid with isooctanol followed by sulfonation and neutralization. The molecular formula is C₂₀H₃₇NaO₇S, and the molecular weight is 444.56.

In terms of product composition, the effective active content of this product is ≥75%, with a diester content of ≥98%, monoester content <2%, free alcohol ≤1%, moisture ≤25%, and extremely strict impurity control. The product appears as a light yellow transparent liquid, with a density of 1.05~1.10 g/cm³ at 25°C and a kinematic viscosity of approximately 150~200 mm²/s, making it a high-purity, high-concentration fast wetting agent. This product is phosphorus-free and exhibits good chemical stability within the pH range of 4~10.

Currently, this product is commonly referred to in the market as fast wetting agent OT-75 or wetting agent T, and its internationally recognized trade name is Aerosol OT-75. As a classic anionic fast wetting agent, DOSS, with its unique diester structure and sulfonate group, endows the product with extremely low surface tension (0.1% aqueous solution: only 26.0~29.0 mN/m) and excellent dynamic wetting ability, making it an indispensable high-efficiency wetting and penetrating auxiliary in many industrial fields such as textiles, pesticides, and daily chemicals.

Main Component Technical Parameters

Parameter ItemSpecification
Core Active IngredientDioctyl sodium sulfosuccinate (DOSS)
CAS Number577-11-7
Ionic TypeAnionic Surfactant
Molecular FormulaC₂₀H₃₇NaO₇S
Molecular Weight444.56
Active Content≥75%
Diester Content≥98%
Monoester Content<2%
Free Alcohol≤1%
Moisture≤25%
AppearanceLight Yellow Transparent Liquid
HLB Value13.5
Phosphorus ContentPhosphorus-Free
Heavy Metals≤10 mg/kg
Arsenic≤3 mg/kg

Application Recommendations

The core value of this high-concentration fast wetting agent lies in its extremely high penetration efficiency — a 0.1% aqueous solution has a canvas sinking time of ≤5 seconds at 25°C, making it one of the fastest penetrating surfactants on the market. In water-based formulation systems, the recommended dosage is typically 0.1%~1.0% of the total formulation weight, and the specific dosage needs to be optimized through gradient tests based on the application scenario and target penetration effect.

This product can be compounded with anionic, nonionic, and some cationic surfactants to achieve synergistic effects. When used as a tank-mix adjuvant in pesticide formulations, it is recommended to dilute to a concentration of 0.025%~0.1% for use, which can significantly enhance the wetting, spreading, and penetration of the spray liquid on plant leaves. This product is a low-foaming type (Roche foam height <50mm), making it particularly suitable for continuous production and circulation systems, reducing reliance on defoamers.

Precautions

  • This product is an anionic surfactant and should not be directly mixed with high-concentration cationic auxiliaries to avoid precipitation or deactivation.
  • The product is stable within the pH range of 4~10, but strong acidic (pH<4) or strong alkaline (pH>10) conditions may cause hydrolysis of the ester bonds, leading to decreased penetration performance.
  • Although it contains approximately 25% moisture, the product is stable under recommended storage conditions. It is advisable to follow the first-in, first-out principle to ensure consistency in batch performance.
  • For specific formulation compatibility, it is recommended to conduct small-scale premixing tests to confirm the absence of layering, turbidity, precipitation, or other anomalies before large-scale production application.