Question

What are emulsifiers OS and MS-1?

Answer
2026-05-17 官方文档 乳化剂OS,MS-1

Emulsifiers OS and MS-1 are two high-performance pesticide-specific emulsifiers launched by Guoli Chemical. OS is of the sodium sec-alkyl sulfonate type (light yellow oily liquid, strong emulsifying power), while MS-1 is of the octylphenol polyoxyethylene ether maleate type (brownish red viscous liquid, excellent comprehensive emulsifying adaptability). The two synergistically cover the processing needs of various pesticide formulations such as emulsifiable concentrates (EC), emulsion in water (EW), suspension concentrates (SC), and microemulsions (ME).

Detailed Description

Emulsifier OS (CAS: 68439-50-9, also known as AEO/Peregal/fatty alcohol polyoxyethylene ether) has the chemical name sodium sec-alkyl sulfonate. It appears as a light yellow to yellowish brown oily liquid and belongs to the nonionic/anionic surfactant type. Its core advantage lies in its extremely strong emulsifying power, enabling rapid formation of stable emulsion systems in either aqueous or oil phases. At the same time, it exhibits excellent wetting, penetration, and dispersing properties, effectively reducing surface tension and preventing active ingredient aggregation. OS has outstanding hard water resistance and good electrolyte stability, making it particularly reliable in pesticide formulations under high-salt or complex water conditions.

Emulsifier MS-1 has the chemical name octylphenol polyoxyethylene ether maleate and appears as a brownish red viscous liquid. MS-1 possesses excellent comprehensive emulsifying performance, compatible with various oil phase systems. Its wetting and spreading properties are prominent, significantly enhancing the spreadability of the spray liquid on target surfaces. Its dispersing and stabilizing effects are long-lasting, delaying formulation stratification, and it has excellent compatibility with various pesticide technical materials and solvents, making it an ideal choice for constructing complex multi-component systems. According to current chemical classification standards, MS-1 is classified as a low-risk chemical with no hazard classification, and its handling safety is superior to that of OS.

Technical Parameters

The following is a comparison of key technical indicators for emulsifiers OS and MS-1 (data source: Guoli Chemical product database):

Parameter ItemEmulsifier OSEmulsifier MS-1
Chemical TypeSodium sec-alkyl sulfonate (nonionic/anionic)Octylphenol polyoxyethylene ether maleate
Appearance (25°C)Light yellow to yellowish brown oily liquidBrownish red viscous liquid
HLB Value12-14
Cloud PointNo cloud pointApprox. 65-75°C (1% aqueous solution)
Active Content≥99%
pH (1% aqueous solution)5.5~7.5
Surface Tension (1% aqueous solution, 25°C)Approx. 30-35 mN/m
Penetration Power (1% aqueous solution, canvas disc method)Approx. 5-15 seconds
Moisture Content≤1.0%
Flash Point (closed cup)>150°C
Acid Value≤1.0 mg KOH/g
Specific Gravity (25°C)Approx. 0.95-1.05 g/cm³
GHS Hazard ClassificationSkin corrosion/irritation Category 2; Serious eye damage/irritation Category 2 (H315, H319)No hazard classification

Application Recommendations

Emulsifiers OS and MS-1 each have their own emphasis in pesticide formulation processing. Proper combination can achieve optimal results:

  • Processing of Emulsifiable Concentrate (EC): OS can quickly dissolve and emulsify the pesticide technical material, improving the stability and dispersibility of the EC; MS-1 is compatible with various oil phase systems. A combination of the two can balance emulsification speed and long-term storage stability.
  • Preparation of Emulsion in Water (EW): OS provides basic emulsification and stabilization, dispersing the oil phase as fine droplets uniformly in the aqueous phase to avoid layering and demulsification, significantly extending the formulation shelf life and reducing