PEG-1000/1500 (CAS No.: 25322-68-3) is a non-ionic polyethylene glycol series product provided by Guoli Chemical, with the molecular formula HO(C₂H₄O)nH, an n value of approximately 20 to 50, corresponding to a molecular weight range of 1000 to 1500. This product is a white waxy solid, easily soluble in water, with a pH value of 4.5 to 7.5 for a 1% aqueous solution, being weakly acidic to neutral. The active content (solid content) of the product is ≥99%, the moisture content is strictly controlled below 1.0%, and the free alcohol content does not exceed 0.5%, ensuring high purity and stability of the product.
From a chemical perspective, the hydroxyl value range of PEG-1000/1500 is 75 to 112 mgKOH/g, acid value ≤0.5 mgKOH/g, saponification value ≤1 mgKOH/g, and iodine value ≤1 gI₂/100g, indicating that the molecular termini are mainly hydroxyl groups, with stable chemical properties, almost no saponifiable ester groups or unsaturated bonds, and resistance to acids, alkalis, and hard water. The HLB value is about 16, making it a highly hydrophilic non-ionic surfactant with good emulsifying, dispersing, and solubilizing capabilities.
In terms of physical properties, its melting point is 37 to 54°C, close to the human body temperature range, which gives it unique advantages in pharmaceutical applications such as suppository bases. At 100°C, the kinematic viscosity is 25 to 35 mm²/s (dynamic viscosity is 30 to 40), density is 1.08 to 1.10 g/cm³, refractive index is 1.458 to 1.460, flash point is above 240°C, making it a substance with low volatility and high thermal stability. The product is hygroscopic and must be stored sealed; under recommended storage conditions, its chemical properties remain stable.
| Parameter Item | Technical Indicator | Remarks |
|---|---|---|
| CAS No. | 25322-68-3 | — |
| Molecular Formula | HO(C₂H₄O)nH | n≈20~50 |
| Molecular Weight | 1000~1500 | Defined distribution range |
| Appearance | White waxy solid | — |
| Ionic Type | Non-ionic | — |
| Active Content (Solid Content) | ≥99% | — |
| Moisture | ≤1.0% | — |
| pH Value (1% Aqueous Solution) | 4.5~7.5 | 25°C |
| pH Value (5% Aqueous Solution) | 4.5~7.5 | 25°C |
| Hydroxyl Value | 75~112 mgKOH/g | — |
| Acid Value | ≤0.5 mgKOH/g | — |
| Saponification Value | ≤1 mgKOH/g | — |
| Iodine Value | ≤1 gI₂/100g | — |
| HLB Value | Approx. 16 | Strong hydrophilicity |
| Melting Point | 37~54°C | Close to body temperature |
| Density (25°C) | 1.08~1.10 g/cm³ | — |
| Kinematic Viscosity (100°C) | 25~35 mm²/s | — |
| Dynamic Viscosity (100°C) | 30~40 | — |
| Refractive Index | 1.458~1.460 | — |
| Flash Point | >240°C | — |
| Hygroscopicity | Hygroscopic | Requires sealed storage |
| Solubility | Easily soluble in water | — |
| Foaming Characteristics | Low foam | — |
| Chemical Stability | Stable | Resistant to acids, alkalis, and hard water |
| Heavy Metals | ≤10 ppm | — |
| Arsenic | ≤2 ppm | — |
| Packaging Specifications | 50kg plastic drum / 200kg plastic drum / IBC tote | Moisture-proof sealed packaging |
Based on the above physicochemical parameters, the application recommendations for PEG-1000/1500 are as follows: Its melting point range of 37 to 54°C makes it particularly suitable for use as a suppository base and drop pill base, capable of rapidly melting and releasing drugs at body temperature; the hydroxyl value of 75 to 112 mgKOH/g indicates sufficient active hydroxyl groups at the molecular termini, which can be used for further chemical modification or as a reaction intermediate; the HLB value of about 16 gives it excellent hydrophilicity, recommended as a humectant and lubricant in cosmetic formulations such as creams and lotions, with a recommended addition amount of 1% to 10%; the high flash point (>240°C) and good thermal stability make it suitable for industrial heat transfer media and high-temperature processing lubrication scenarios.