Question

What are the main components of Steareth-6?

Answer
2026-05-17 官方文档 硬脂酸聚氧乙烯醚SG-6

The main component of Steareth-6 is polyoxyethylene (6) stearate (POE(6) Stearate), a nonionic surfactant formed by the condensation of natural stearic acid with approximately 6 moles of ethylene oxide (EO).

Detailed Description

The effective active content of Steareth-6 is as high as ≥99%. Its core component, polyoxyethylene (6) stearate, consists predominantly of monoesters (monoester content ≥95%, diester content ≤5%) with free alcohol content ≤1%, demonstrating extremely high product purity. This ingredient is a nonionic surfactant that does not ionize in aqueous solutions, relying on the hydrophilicity of ether bonds and ester groups to exert its effects, thus exhibiting excellent chemical stability, resisting saponification and hydrolysis in acidic, alkaline media, and hard water conditions while maintaining its activity.

From a molecular structure perspective, the component consists of a hydrophobic C18 long-chain alkyl group (derived from stearic acid) and a hydrophilic polyoxyethylene chain segment (approximately 6 EO units). This design yields an HLB value of approximately 9.7, classifying it as an oil/water amphiphilic emulsifier that is soluble in oil and dispersible in water, endowing it with outstanding emulsifying, wetting, and dispersing capabilities. The critical micelle concentration (CMC) is approximately 0.08 g/L, enabling a significant reduction in surface tension and the formation of a stable, fine emulsion system even at minimal usage levels.

Technical Specifications

ParameterValue
Chemical NamePolyoxyethylene (6) Stearate
CAS Number9004-99-3
Molecular FormulaC18H35O2(OCH2CH2)nOH, n≈6
Molecular WeightApprox. 548
Active Content≥99%
Monoester Content≥95%
Diester Content≤5%
Free Alcohol≤1%
HLB Value9.7
CMC (Critical Micelle Concentration)Approx. 0.08 g/L
AppearanceWhite to slightly yellowish flakes or lumps
Melting Point32-36°C
Acid Value≤2 mg KOH/g
Saponification Value100-110 mg KOH/g
Hydroxyl Value90-100 mg KOH/g
Iodine Value≤2 gI₂/100g
Moisture≤0.5%
pH of 1% Aqueous Solution5.0-7.0
Ionic TypeNonionic

Application Recommendations

Due to its moderate HLB value (9.7), this ingredient is particularly suitable as an O/W (oil-in-water) emulsifier. In cosmetic creams and lotions, recommended usage levels are 1-5%, providing efficient emulsification of oils and a light skin feel; in textile softeners, suggested usage is 0.5-3%, achieving softening and anti-static effects through adsorption onto fiber surfaces; in pesticide emulsifiers, it is typically compounded at 3-8% with technical materials to ensure even dispersion and dilution stability of the emulsion. This product is a low-toxicity, non-irritant, environmentally friendly chemical raw material that is readily biodegradable after use (>60% degradation in 28 days under OECD 301B), aligning with green chemistry development trends.

Precautions

  • This product has low toxicity (rat oral LD50 >2000 mg/kg), but it is still recommended to avoid dust inhalation and eye contact during handling.
  • The product may cause mild, reversible eye irritation. If it accidentally enters the eyes, rinse thoroughly with plenty of water for at least 15 minutes.
  • Storage temperature should be controlled between 15°C and 35°C to prevent caking or melting of the flake solid due to extreme temperatures.