Polysorbate 61 (Tween 61) – Low-EO Stearate Emulsifier

Overview

Chemical Nature

Specialized stearate surfactant with a shorter ethylene oxide chain (4 moles) than Tween 60.
Appearance & Specs

Waxy solid | HLB Value: 9.6
★ Primary Application (Cosmetics)

Structural Body Builder. Unlike liquid Polysorbates, its waxy nature makes it an excellent co-emulsifier and thickening agent, providing richness to creams.
Industrial Use

Effective stabilizer for industrial wax dispersions.
Key Functions

Co-emulsifier & Thickening Agent.

Molecular Structure

Structural Components

Hydrophilic Segment: Polyoxyethylene chain introduced by ethoxylation (4 moles as per formula), enhancing water solubility.

Hydrophobic Moiety: Stearic acid chain derived from long-chain fatty acids, providing oil affinity.

Backbone: Sorbitan formed by dehydrated sorbitol, linking the hydrophilic and hydrophobic groups.
★ Mechanism of Action

Amphiphilic Positioning. This structure allows Polysorbate 61 to position itself effectively at the oil–water interface. It significantly reduces surface tension and stabilizes emulsions.

Specifications:

Polysorbate 61 is generally presented as a waxy or semi-solid material, with a characteristic mild odor. Its hydrophilic-lipophilic balance (HLB) is lower than other polysorbates with higher ethoxylation degrees, making it particularly useful for stabilizing oil-in-water systems with higher oil content. It also shows good compatibility with other emulsifiers such as sorbitan esters, enabling synergistic effects in multi-component emulsification systems.

Test Indicator	Unit	Min Value	Max Value
HLB value	——	9.6
Saponification Value	mgKOH/g	95	115
Hydroxyl Value	mgKOH/g	165	195
Acid Value	mgKOH/g	-	3
HLB	-	-	9.6

Download TDS

Applications:

Cosmetics (Barrier Creams): Used in heavy moisturizing creams and sunscreens to provide a protective, water-resistant barrier and increase viscosity.
Industrial Polishes: Acts as an emulsifier in car waxes, furniture polishes, and leather dressings where a solid waxy residue is desirable.
Textile & Leather: Used as a lubricant and softener in fiber processing.

Intermediate HLB (9.6)

With an HLB of 9.6, Polysorbate 61 sits perfectly between oil-soluble Spans and water-soluble Tweens. This makes it a powerful ‘coupling agent’ to stabilize complex oil-water interfaces.

Solid Waxy Structure

Being a solid at room temperature, it naturally builds viscosity and body in formulations, reducing the need for additional thickeners or hard waxes.

Water Resistance

Due to its lower ethylene oxide content (only 4 moles), it is less water-soluble than Tween 60, making it ideal for formulating water-resistant sunscreens and protective barrier creams.

Stearate Compatibility

Highly compatible with fatty alcohols and other stearate-based ingredients, ensuring smooth, glossy, and stable white emulsions.

Solid waxy flakes of Polysorbate 61 surfactant, highlighting its solid physical state compared to liquid emulsifiers.

Thick, protective barrier cream texture, demonstrating the viscosity-building properties of Polysorbate 61 in skincare.

storage & package:

Storage:
Store in a cool, dry, and well-ventilated area, away from direct sunlight and sources of heat.
Avoid contact with harmful or incompatible substances. Handle with care during transportation to prevent leakage or contamination.

Transportation:
Transport as a general chemical product, following standard safety and handling procedures.

Package:
Polysorbate 61 is packed in high-quality PE drums with double-seal lids.
Standard packaging sizes include 25kg/drum, 200kg/drum, and 1000kg IBC tote to meet different usage needs.