Polyoxyethylene Stearate SG-9 (PEG-9 Stearate) is a chemically stable nonionic surfactant, resistant to acids, alkalis, and hard water, and is not prone to deterioration under conventional storage environments. However, due to its appearance as a white to light yellow flaky solid (melting point 28–35°C), softening or caking may occur at higher temperatures, making storage temperature control particularly critical.
When stored unopened and strictly under recommended conditions, the recommended shelf life of this product is 2 years (from the date of manufacture). After the shelf life expires, it is recommended to sample and test key indicators (such as acid value ≤2 mgKOH/g, saponification value 90–100 mgKOH/g, moisture ≤0.5%, etc.) to confirm performance before continued use. Currently, the Guoli Chemical product database has no official statement on a specific shelf life; the above recommendation is based on the product's chemical stability and common industry practices.
| Storage Condition | Specific Requirements |
|---|---|
| Storage Temperature | Should not exceed 35°C; avoid large temperature differences to prevent caking or softening |
| Environmental Requirements | Cool, dry, well-ventilated; avoid direct sunlight and moisture |
| Container Sealing | Container must be kept sealed to prevent moisture absorption and foreign matter entry |
| Materials to Avoid | Keep away from heat sources, ignition sources, and incompatible substances (such as strong oxidizers and strong acids) |
| Recommended Packaging Materials | Stainless steel drums, polyethylene drums, fiber drums with plastic liners |
| Leak Prevention Measures | Storage area should be equipped with leak prevention facilities and containment materials (such as inert absorbents) |
| Access Management | Unauthorized personnel shall not enter the storage area; limited storage quantities shall be implemented |
After opening the container, reseal the remaining product as soon as possible to avoid prolonged exposure to air and moisture absorption. If abnormal conditions such as significant color darkening, severe caking, or unusual odors are observed, it is recommended to stop use and perform quality re-inspection. For bulk purchases, it is advisable to follow the "first-in, first-out" principle to ensure inventory products are always circulated within their validity period.
This product has low hygroscopicity, but prolonged exposure to high humidity environments may still cause moisture absorption leading to caking, affecting ease of use and dosing accuracy. In addition, frequent temperature fluctuations in storage may cause the product surface to "sweat" or partially melt and then re-solidify; it is recommended to keep the warehouse temperature within a relatively constant range. Although the product is not classified as a hazardous chemical and poses no special risks during conventional transportation, exposure to high temperatures, sunlight, rain, and moisture should still be avoided.