Tween T-60 (Polyoxyethylene (20) sorbitan monostearate, Polysorbate 60) is a stable nonionic surfactant, but its application effect is influenced by temperature, pH value, electrolytes, and operating procedures. You can quickly troubleshoot based on the following high-frequency issues:
Poor emulsification/solubilization effect or stratification: First, confirm the HLB value compatibility—Tween T-60 has an HLB value of 14.9, suitable for oil-in-water (O/W) emulsion systems. If the required HLB value of the oil phase differs significantly from the emulsifier's HLB value, emulsification efficiency will decrease. Second, check the cloud point temperature; the cloud point of a 1% aqueous solution is 76~78°C. Operating temperature should not be close to or exceed this temperature for prolonged periods, otherwise the nonionic surfactant will dehydrate and precipitate, losing its emulsifying ability.
Poor dissolution or uneven dispersion of the product: Tween T-60 is a viscous liquid or paste at room temperature, with a freezing point of about 20~25°C. The viscosity increases significantly at low temperatures (kinematic viscosity at 25°C is 400~600 mm²/s). If taken directly from a cold storage, it is recommended to warm the material to a flowable state in an environment of 25~35°C, then slowly add it to the water phase under stirring. Do not add a large amount at once to avoid forming "fish-eye" agglomerates that are difficult to disperse.
Abnormal color or odor of the product: The normal product is light yellow to amber. If the color noticeably deepens or rancid odor appears, it may be due to oxidation or hydrolysis caused by improper storage. Check storage conditions: whether it is sealed, protected from light, and at a temperature between 5~35°C, and whether it is stored together with strong acids or strong bases. The acid value of this product should be ≤2.0. If the acid value increases significantly, it is recommended to stop use and send a sample for testing.
| Parameter item | Specification or value |
|---|---|
| Chemical type | Nonionic surfactant |
| HLB value | 14.9 |
| Cloud point (1% aqueous solution) | 76~78°C |
| Freezing point | Approx. 20~25°C |
| pH value (1% aqueous solution) | 5.0~7.0 |
| Acid value | ≤2.0 |
| Saponification value | 45~55 |
| Hydroxyl value | 81~96 |
| Kinematic viscosity (25°C) | 400~600 mm²/s |
| Surface tension (1% aqueous solution, 25°C) | 42~45 mN/m |
| Critical micelle concentration (CMC) | Approx. 3×10⁻⁵ mol/L |
| Water content | ≤3.0% |
| Heavy metal content | ≤10 mg/kg |
| Arsenic content | ≤2 mg/kg |
To ensure optimal use, please refer to the following process guidance:
If the problem remains unresolved after following the above steps, or if you encounter complex formulation issues, need sample re-testing, or require customized application solutions, please contact the technical team of Hai'an County Guoli Chemical Co., Ltd. through the following channels:
Tip: Tween T-60 is a food grade and pharmaceutical grade nonionic surfactant. If used in sensitive fields, be sure to request the corresponding batch inspection report (COA) and compliance statement documents in advance.