Question

How to use Polyether L-61? What is the recommended dosage?

Answer
2026-06-06 官方文档 聚醚L-61

The usage method and dosage of Polyether L-61 vary depending on the specific application. It is generally recommended to add it through premixing or dilution, with a typical dosage range of 0.1% to 5%. The optimal dosage should be determined through experiments based on the actual process.

Detailed Description

Polyether L-61 (Poloxamer 181) is a low-foaming nonionic surfactant with an HLB value of approximately 3. It is lipophilic, insoluble in water but dispersible, and soluble in organic solvents such as ethanol and ether. Therefore, in practical use, it is recommended to premix it thoroughly with the oil phase or organic solvent before slowly introducing it into the aqueous system to ensure full dispersion and achieve optimal emulsification, defoaming, or foam stabilizing effects. Directly adding it to an aqueous system may lead to uneven dispersion and reduce efficiency.

This product has an active content of ≥99.5%, a density of about 1.02 g/cm³ (25°C), a viscosity of about 400 mPa·s (25°C), a low freezing point of approximately -29°C, and a flash point >200°C. It exhibits good fluidity under normal operating conditions, making it easy to meter and pump. It maintains stable interfacial activity over a wide pH range and in hard water conditions, adapting to various complex formulation systems.

Technical Parameters

ParameterValue/Description
AppearanceColorless to light yellow transparent liquid
Active Content≥99.5%
HLB ValueApprox. 3
Molecular WeightApprox. 2000
Density (25°C)Approx. 1.02 g/cm³
Viscosity (25°C)Approx. 400 mPa·s / Approx. 400 mm²/s
pH Value (1% Aqueous Solution)5.0–7.5
Hydroxyl ValueApprox. 28 mg KOH/g
Flash Point>200°C
Freezing PointApprox. -29°C
SolubilitySoluble in organic solvents, insoluble in water
Foaming CharacteristicsLow foaming

Application Recommendations

The following dosages are industry general reference ranges (source: Guoli Chemical product database and application experience; specific amounts need to be confirmed through actual experiments):

Application FieldRecommended Dosage (by weight of total formulation)Usage Method
Polyurethane flexible foam stabilizer0.5%–2.0%Premix thoroughly with the polyol component before foaming
Polyurethane rigid foam emulsification and dispersion aid1.0%–3.0%Add to the polyol or blowing agent premix and stir uniformly
Active component in industrial defoamers5.0%–20.0% (in the defoamer formulation)Compound with carrier oil, emulsifiers, etc., as the main active substance
Final use concentration of defoamer0.05%–0.5% (in the process medium)Dilute with water or solvent in advance, then slowly add to the foaming system
Antifoam and lubricating component in water-based metalworking fluids0.5%–3.0%Add to base oil or concentrate, stir and mix evenly in circulation
Low-foaming penetrant/leveling agent in textiles0.1%–1.0% (based on working solution weight)Pre-disperse with a small amount of warm water or alcohol, then add to the dye bath
Emulsification dispersant in pesticide formulations1.0%–5.0% (in the formulation)Premix with oil-soluble active ingredients and solvents to prepare emulsifiable concentrate or suspension concentrate

Precautions

  • Premixing is key: Since Polyether L-61 is insoluble in water, direct addition to the aqueous phase may cause uneven dispersion. It is strongly recommended to premix it with the oil phase or organic solvent before introducing it into the aqueous system.
  • Dosage requires experimental confirmation: The above dosages are general reference ranges. The actual optimal dosage depends on the formulation system, process conditions, and performance requirements. It is recommended to determine it through gradient experiments.
  • Operational safety: Wear chemical safety goggles and chemical-resistant gloves (nitrile rubber or neoprene) during operation. Use in a well-ventilated area, avoid inhaling vapor or prolonged skin contact. In case of eye contact, rinse immediately with plenty of water for at least 15 minutes and seek medical attention.
  • Storage conditions: Store in a cool, dry, and well-ventilated place at 5–40°C. Keep the container tightly sealed, away from strong oxidizers and ignition sources. The freezing point is about -29°C, and the product remains flowable at low temperatures.