Stearic Acid Polyoxyethylene Ether SG-6 (CAS No.: 9004-99-3), chemical name polyoxyethylene (6) stearate, is a nonionic surfactant. The product appears as a white to slightly yellow flake or block solid, with a melting point of 32–36°C, an HLB value of 9.7, and a cloud point (1% aqueous solution) of 28–32°C. It is an emulsifier variety with balanced hydrophilic and lipophilic properties. The molecular structure of this product is based on stearic acid added with about 6 moles of ethylene oxide, with a molecular weight of approximately 548. It has excellent chemical stability and is resistant to acids, alkalis, and hard water.
This product is dispersed or slightly soluble in water but readily soluble in ethanol, acetone, and oily organic solvents. It can be used as an O\/W emulsifier and can also be compounded with anionic, cationic, and amphoteric surfactants for synergistic effects. Due to its low toxicity, non-irritating nature, and easy biodegradability, this product is widely used in high-end fields such as cosmetics, textiles, pesticides, industrial cleaning, and metalworking fluids.
The following physicochemical technical parameters are all derived from actual measurement data in the Guoli Chemical Product Database, covering routine factory inspection indicators and performance characterization parameters:
| Parameter Item | Technical Indicator | Remarks |
|---|---|---|
| Appearance | White to slightly yellow flake or block solid | Visual method |
| Melting Point | 32–36°C | —— |
| Density | Approx. 0.98 g\/cm³ | Room temperature condition |
| Refractive Index | 1.450–1.460 | —— |
| Kinematic Viscosity | Approx. 40 mPa·s (40°C) | Low shear viscosity |
| Flash Point | >180°C (closed cup) | Non-flammable |
| Hygroscopicity | Low | —— |
| Parameter Item | Technical Indicator | Remarks |
|---|---|---|
| Solubility | Easily soluble in ethanol, acetone, oils; slightly soluble in water | Dispersed state in water |
| HLB Value | 9.7 | Hydrophilic-lipophilic balance value |
| Cloud Point (1% aqueous solution) | 28–32°C | —— |
| Critical Micelle Concentration (CMC) | Approx. 0.08 g\/L | —— |
| Surface Tension | Approx. 30 mN\/m | Under CMC condition |
| Foaming Characteristics | Low foaming | —— |
| Parameter Item | Technical Indicator | Remarks |
|---|---|---|
| Active Content | ≥99% | —— |
| Monoester Content | ≥95% | —— |
| Diester Content | ≤5% | —— |
| Free Alcohol Content | ≤1% | —— |
| Moisture | ≤0.5% | —— |
| Acid Value | ≤2 mg KOH\/g | —— |
| Saponification Value | 100–110 mg KOH\/g | —— |
| Hydroxyl Value | 90–100 mg KOH\/g | —— |
| Iodine Value | ≤2 g I₂\/100g | Very low unsaturation |
| pH Value (1% aqueous solution) | 5.0–7.0 | —— |
| pH Value (5% aqueous solution) | 5.0–7.0 | —— |
| Total Heavy Metals | ≤10 mg\/kg | —— |
| Arsenic (As) | ≤2 mg\/kg | —— |
| Chemical Stability | Stable, resistant to acids, alkalis, and hard water | Not saponified, not hydrolyzed |
| Parameter Item | Technical Indicator | Remarks |
|---|---|---|
| Acute Oral Toxicity LD₅₀ (Rat) | >2000 mg\/kg | Low toxicity |
| Skin Irritation (Rabbit) | PII <0.5, non-irritating | 4h closed patch |
| Eye Irritation (Rabbit) | Mild reversible irritation | Recovery within days |
| Skin Sensitization (Guinea Pig) | Sensitization rate 0%, no sensitization | —— |
| Ecotoxicity (Fish 96h LC₅₀) | >100 mg\/L | —— |
| Ecotoxicity (Daphnia 48h EC₅₀) | >100 mg\/L | —— |
| Ecotoxicity (Algae 72h ErC₅₀) | >100 mg\/L | —— |
| Biodegradability (OECD 301B) | Degradation rate >60% in 28 days | Readily biodegradable |
| Bioaccumulation Potential | No bioaccumulation potential | —— |
Based on the HLB value of 9.7 and excellent emulsifying, wetting, and dispersing properties, SG-6 is an ideal choice for O\/W emulsifying systems, especially suitable for formulation scenarios requiring compounding with anionic or amphoteric surfactants. In cosmetic creams and lotions, the recommended dosage is 1%–4% of the total formulation, and it can be used with fatty alcohol thickeners to improve the viscosity stability of the system. For textile softening finishing, the recommended dosage is 2–5 g\/L at a temperature controlled at 40–50°C, and it can be used alone or compounded with amino silicone microemulsion. In pesticide emulsion concentrates, as an emulsifier component, the recommended dosage is 3%–8% (of the total formulation), and it can be compounded with anionic emulsifiers such as calcium salt.