The Guoli Chemical Polyethylene Glycol PEG-4000/6000 (CAS No.: 25322-68-3) series belongs to high-molecular-weight nonionic polymers with a molecular weight range of 3400~6600. Compared with low-molecular-weight liquid PEG (such as PEG-200/400), PEG-4000/6000 is a white waxy solid with a melting point as high as 50~63°C, enabling unique functions such as solid excipient and hot-melt processing. It is particularly suitable for applications requiring specific melting point characteristics, such as pharmaceutical suppository bases, drip pill carriers, and rubber mold release agents.
From the technical specifications, the active content of PEG-4000/6000 is ≥99%, moisture content ≤1.0%, acid value ≤0.1, and iodine value ≤1. These stringent controls on key impurities ensure the reliability of the product in precision applications. Compared with some low-purity competitive products on the market, its extremely low ash content allows it to serve as a lubricating component in cutting fluids for precision metal processing without leaving residues on the workpiece surface. Additionally, its HLB value is as high as 18.9~19.0, and the cloud point is >100°C, endowing the product with excellent water solubility and compatibility, enabling good miscibility with various formulation systems.
In terms of safety, the acute oral toxicity LD50 of PEG-4000/6000 is greater than 5000 mg/kg, classifying it as a practically non-toxic substance, far superior to many similar functional additives with significant irritation or toxicity. It remains stable over a wide pH range and exhibits excellent tolerance to acids, bases, and hard water environments, which is notably superior to some ester or amide additives that are prone to hydrolysis under acidic or alkaline conditions. However, it should be noted that its fine dust, when mixed with air to a certain concentration, poses a risk of dust explosion (St1 level). Operating areas should maintain good ventilation and be equipped with dust collection systems.
| Technical Index | Value | Description |
|---|---|---|
| Molecular Weight Range | 3400~6600 | High molecular weight solid, providing excellent formability |
| Ion Type | Nonionic | Widely compatible with various systems |
| HLB Value | 18.9 / 19.0 | Extremely high hydrophilicity, excellent water solubility |
| Active Content | ≥99% | High purity, extremely low impurities |
| Melting Point | 50~63°C | Suitable for hot-melt processing and solid excipient applications |
| Moisture | ≤1.0% | Low moisture content ensures storage stability |
| Acid Value | ≤0.1 mgKOH/g | Extremely low acidity, no interference with formulation system |
| Hydroxyl Value | 8~16 mgKOH/g | Controllable terminal hydroxyl content |
| Iodine Value | ≤1 | Nearly saturated, excellent oxidation stability |
| Density | 1.20~1.21 g/cm³ | Derived from database |
| pH Value (1% Aqueous Solution) | 5.0~7.0 | Near neutral, wide application range |
| Cloud Point | ＞100°C | Remains water-soluble at high temperatures, good thermal stability |
| Flash Point (Open Cup) | ＞240°C | High flash point, good processing safety |
| Acute Oral Toxicity LD50 | ＞5000 mg/kg | Practically non-toxic, extremely high safety |
| Heavy Metal Content | ≤10 ppm | Complies with pharmaceutical and daily chemical standards |
| Arsenic Content | ≤2 ppm | Complies with pharmaceutical and daily chemical standards |
Based on its unique technical characteristics, the recommended applications of PEG-4000/6000 in different industries are as follows:
Based on its technical parameters and application performance, the core advantages of PEG-4000/6000 over similar products are: High purity with low impurities (content ≥99%, acid value ≤0.1) ensures no residue in precision applications; High thermal stability and high cloud point (cloud point >100°C, flash point >240°C) performs excellently in high-temperature processing; High safety and low toxicity (LD50 >5000 mg/kg) makes it the preferred basic material in pharmaceutical and daily chemical fields; Extremely strong chemical stability maintains functional integrity over a wide pH range.