Polyethylene glycol PEG-2000 (CAS No.: 25322-68-3) is a linear polymer compound polymerized from ethylene oxide, with the molecular formula HO(C₂H₄O)nH, a degree of polymerization n of about 20~50, and an average molecular weight range of 1800~2200. The product carries active hydroxyl groups at the ends, which can serve as precursors for esterification/etherification reactions, used to synthesize a series of non-ionic surfactants such as polyethylene glycol fatty acid esters and polyethers.
At room temperature, this product is a white to off-white waxy solid or flake with uniform color. Upon melting, it becomes a transparent viscous liquid, and upon cooling, it returns to a solid state, exhibiting good thermal reversibility. Its non-ionic nature allows it to be well compatible with anionic, cationic, and other non-ionic substances. It maintains stable performance over a wide pH range (pH 4.5~7.5 for a 1% aqueous solution) and under different water quality conditions, with excellent resistance to acid, alkali, and hard water.
With its excellent hygroscopicity and water retention capacity, PEG-2000 is widely used in industries such as pharmaceuticals, cosmetics, textiles, papermaking, metal processing, coatings, and inks. Its flash point is >240℃, and it is not classified as a dangerous chemical. Under normal use conditions, it is non-irritating to skin and eyes and has high safety.
| Parameter Item | Technical Indicator | Data Source |
|---|---|---|
| CAS No. | 25322-68-3 | Guoli Chemical Product Database |
| Molecular Formula | HO(C₂H₄O)nH, n≈20~50 | Guoli Chemical Product Database |
| Average Molecular Weight | 1800~2200 | Guoli Chemical Product Database |
| Appearance | White to off-white waxy solid or flake | Guoli Chemical Product Database |
| Ion Type | Non-ionic | Guoli Chemical Product Database |
| HLB Value | 20 | Guoli Chemical Product Database |
| Melting Point | 45~55℃ | Guoli Chemical Product Database |
| Density | 1.21 g/cm³ | Guoli Chemical Product Database |
| Flash Point | >240℃ (Closed cup method) | Guoli Chemical Product Database |
| Kinematic Viscosity | 50~65 mm²/s (100℃) | Guoli Chemical Product Database |
| Refractive Index | 1.459 (60℃, molten state) | Guoli Chemical Product Database |
| Cloud Point | >100℃ (1% aqueous solution) | Guoli Chemical Product Database |
| Surface Tension | Approx. 63 mN/m (1% aqueous solution, 25℃) | Guoli Chemical Product Database |
| pH Value (1%/5% aqueous solution) | 4.5~7.5 | Guoli Chemical Product Database |
| Active Content/Solid Content | ≥99% | Guoli Chemical Product Database |
| Hydroxyl Value | 51~62 mg KOH/g | Guoli Chemical Product Database |
| Acid Value | ≤0.5 mg KOH/g | Guoli Chemical Product Database |
| Saponification Value | ≤1 | Guoli Chemical Product Database |
| Iodine Value | ≤1 | Guoli Chemical Product Database |
| Moisture Content | ≤0.5% | Guoli Chemical Product Database |
| Heavy Metals | ≤5 mg/kg | Guoli Chemical Product Database |
| Arsenic | ≤2 mg/kg | Guoli Chemical Product Database |
| Water Solubility | Easily soluble in water | Guoli Chemical Product Database |
| Hygroscopicity | Hygroscopic | Guoli Chemical Product Database |
| Foaming Properties | Low foaming | Guoli Chemical Product Database |
| Chemical Stability | Stable, incompatible with strong oxidizers | Guoli Chemical Product Database |
| Critical Micelle Concentration (CMC) | None | Guoli Chemical Product Database |
| Packaging Specifications | 200kg iron drum, 50kg plastic drum | Guoli Chemical Product Database |
Pharmaceutical Field: Utilizing its suitable melting point range (45~55℃) and good water solubility, it is recommended for use as a suppository base, ointment base, and pill matrix. In tablet preparation, it can be used as a binder and lubricant, with the recommended dosage adjusted according to the specific formulation process. When used as a solubilizer for injections, special attention should be paid to compliance with heavy metal (≤5 mg/kg) and arsenic (≤2 mg/kg) indicators.
Cosmetics and Personal Care Products: With an HLB value of 20 for hydrophilic properties and excellent hygroscopicity, it is recommended for use in formulations such as moisturizing creams, lotions, and cleansing products as a humectant and emollient. Its low foaming property makes it suitable for use in low-foam or foam-free formulations, and it has good compatibility with various types of surfactants.
Industrial Applications: In the textile industry, it serves as an antistatic agent and softener, forming a hydrophilic film on the fiber surface due to its water solubility; in metalworking fluids, it acts as a lubricating enhancer, with kinematic viscosities of 50~65 mm²/s at 100℃ providing good high-temperature lubrication performance; in paint and ink systems, it is used as a dispersant and rheology modifier, facilitating the uniform dispersion of pigments and fillers.