Polypropylene glycol PPG-400 (CAS number: 25322-69-4) is a non-ionic surfactant produced by catalytic polymerization of propylene oxide and propylene glycol. It appears as a colorless to slightly yellow transparent viscous liquid. The ether bonds and terminal hydroxyl groups in its molecular structure endow the product with unique solubility and reactivity, making it a key intermediate and functional component in many industrial formulations.
The outstanding advantages of this product are reflected in six aspects: First, excellent surface activity, with outstanding emulsifying, wetting, dispersing, and solubilizing capabilities, effectively reducing interfacial tension; Second, superior chemical stability, performing well in acidic, alkaline, and hard water media, not easily hydrolyzed or deactivated; Third, as a reactive intermediate, it has high primary hydroxyl content and moderate reactivity, making it a high-quality synthetic raw material for polyurethane, ester derivatives, etc.; Fourth, outstanding safety, with an acute oral LD₅₀ greater than 2000 mg/kg, non-irritating to the skin, causing only mild and transient irritation to the eyes, and non-sensitizing; Fifth, long-lasting lubricating and moisturizing properties, with stable viscosity-temperature characteristics, providing stable performance over a wide temperature range; Sixth, low hygroscopicity, and excellent compatibility with various organic solvents, resins, and polymers.
Based on these characteristics, PPG-400 is used in the polyurethane industry as a soft segment component to provide flexibility and hydrolysis resistance; in synthetic lubricating oils as a base oil or co-solvent; in daily chemicals as a moisturizer, lubricant, and solubilizer; in the pharmaceutical field as a suppository base and drug solubilizer; also as a core raw material for defoamers and release agents.
| Parameter Item | Parameter Description |
|---|---|
| Product Name | Polypropylene Glycol PPG-400 |
| CAS Number | 25322-69-4 |
| Aliases | Polyoxypropylene diol, Polypropylene oxide, PPG 400, Polypropylene glycol 400, PAG 400 |
| Product Type | Non-ionic Surfactant |
| Appearance | Colorless to slightly yellow transparent viscous liquid |
| Molecular Weight | Approximately 400 (MW 400) |
| Flash Point (Closed Cup) | Approximately 220–230°C |
| Acute Oral Toxicity (LD₅₀) | >2000 mg/kg (Low toxicity) |
| Skin Irritation | Non-irritating (New Zealand white rabbit test) |
| Sensitization | Non-sensitizing (Guinea pig Buehler test negative) |
| Biodegradability | Not readily biodegradable (OECD 301B 28-day degradation rate ≤20%) |
| Aquatic Toxicity | Low toxicity (Fish, daphnia, algae L(E)C₅₀ all >100 mg/L) |
| Recommended Storage Temperature | 0–40°C |
| Shelf Life | Not less than 12 months |
Select recommended dosage according to specific use: In polyurethane formulations, PPG-400 participates in the reaction as a soft segment polyol component, and the dosage needs to be adjusted based on the hard segment ratio and required flexibility; in lubricating oil formulations, it can be added as a base oil or co-solvent at 5%–50%; in cosmetic creams and lotions, the recommended addition amount is 1%–10% to enhance moisturizing properties and skin feel; in pharmaceutical suppository and ointment bases, the dosage is adjusted according to the required consistency. As a raw material for defoamers and release agents, it is usually used in combination with other components.