Tween 81, chemically known as Polyoxyethylene (5) Sorbitan Monoleate, is a non-ionic surfactant widely used in industries like pharmaceuticals, cosmetics, and food. Derived from sorbitol, oleic acid, and ethylene oxide, it features good solubility in water and organic solvents.
Its core functions include emulsification (stabilizing oil-water mixtures), solubilization (enhancing solubility of lipophilic substances), and wetting. In pharmaceuticals, it aids drug delivery; in cosmetics, it improves product texture; in food, it acts as an emulsifier. It’s generally considered safe with low toxicity, making it a versatile additive in various formulations.
Product Advantage
Superior Emulsification Stability with Quantifiable Performance
Tween 81 exhibits exceptional emulsifying efficiency, maintaining stable oil-water emulsions for over 12 months at 25°C without phase separation—verified by accelerated stability tests (40°C/75% RH for 3 months). Its HLB value of 10.0 is precisely calibrated to balance lipophilic and hydrophilic properties, making it ideal for middle-phase emulsions, which reduces formulation failure rates by 30% compared to generic non-ionic surfactants.
Low Toxicity & Regulatory Compliance for Multi-Industry Use
With an LD50 (oral, rat) of >20,000 mg/kg, Tween 81 meets the strict safety standards of FDA (21 CFR §172.840), EU ECOCERT, and China GB 2760. It is free from heavy metals (<10 ppm lead/cadmium) and residual solvents (<500 ppm), enabling direct application in pharmaceuticals (oral formulations) and food (dairy products) without additional purification.
Broad Solubility & Compatibility Across Formulations
Unlike many surfactants, Tween 81 dissolves readily in both water (solubility: >100 g/L at 25°C) and organic solvents (ethanol, propylene glycol, mineral oil), eliminating the need for co-solvents. It also shows excellent compatibility with active pharmaceutical ingredients (APIs), polymers, and preservatives—compatibility tests confirm no precipitation or degradation when mixed with 95% of common cosmetic and pharmaceutical raw materials, simplifying formulation development.
Controlled Ethylene Oxide (EO) Chain for Targeted Functionality
Tween 81 is synthesized with a precisely controlled 5-mole EO chain (vs. Tween 80’s 20-mole chain), which optimizes its wetting and dispersing capabilities. This shorter chain reduces surface tension to 35 mN/m (at 0.1% concentration), enhancing the spreadability of cosmetic creams and improving drug dissolution rates by 25% in oral suspensions—critical for poorly water-soluble APIs.
Consistent Quality with Strict Manufacturing Standards
Our Tween 81 is produced via a continuous stirred-tank reactor (CSTR) process with in-line quality monitoring, ensuring batch-to-batch consistency: acid value (<2.0 mg KOH/g), saponification value (135–150 mg KOH/g), and hydroxyl value (190–210 mg KOH/g) all meet USP/NF Grade specifications. Each batch undergoes 12 quality checks, with a pass rate of 99.8% over the past 3 years, minimizing supply chain risks for customers.
Sustainable Production & Environmental Friendliness
The raw materials for Tween 81 (sorbitol, oleic acid) are derived from renewable sources (corn starch, palm oil), with a bio-based carbon content of >70% (per ASTM D6866). Our production process reduces water consumption by 40% and carbon emissions by 25% compared to traditional methods, and the product is readily biodegradable (90% degradation within 28 days per OECD 301B test), aligning with global sustainability goals.
Technical Parameters
| Parameter | Specification |
| Chemical Name | Polyoxyethylene (5) sorbitan monoaleate |
| Appearance | Yellow to amber viscous liquid |
| Lonicity | Non-ionic |
| Hydroxyl Value | 135~165 mg KOH/g |
| Saponification Value | 90~105 mg KOH/g |
| Acid Value | ≤ 2.0 mg KOH/g |
| Water Content | ≤ 3.0% |
| HLB Value | 10 |
Product Uses
Used in oral suspensions (e.g., antibiotic suspensions) to solubilize poorly water-soluble APIs, boosting dissolution rates by 25%. Also added to injectable emulsions (e.g., fat emulsions) as a stabilizer, preventing phase separation during storage and ensuring drug delivery safety.
2.Cosmetics & Personal Care
Applied in creams, lotions, and sunscreens. It acts as an emulsifier to blend oil-based ingredients (e.g., plant oils) with water, enhancing product texture and spreadability. In hair conditioners, it improves wet combing by reducing surface tension of hair strands.
Serves as an emulsifier in dairy products (e.g., ice cream, whipped cream) to stabilize air bubbles, preventing crystallization and extending shelf life. Also used in salad dressings to mix oil and vinegar, maintaining a uniform texture without layering.
Added to pesticide formulations (e.g., herbicide sprays) as a wetting agent. It lowers the surface tension of spray droplets, enabling better adhesion to crop leaves, thus improving pesticide efficacy and reducing waste.
Incorporated into industrial degreasers and metal cleaners. Its solubilizing and wetting properties help break down oil and grease deposits on machinery surfaces, ensuring thorough cleaning while being compatible with most metal materials (e.g., steel, aluminum) without corrosion.
Product Operate Guide
1、For Pharmaceuticals
Add 0.5–2% Tween 81 to API mixtures. Heat to 40–50°C, stir at 300–500 rpm until dissolved. Blend with aqueous phase slowly for suspensions; for injectables, use sterile grade and filter post-mixing.
2、For Cosmetics
Mix 1–3% Tween 81 with oil phase first. Heat to 60–70°C, then combine with heated water phase (same temp). Stir at 200 rpm until cooled to 30°C for smooth textures.
3、For Food
Incorporate 0.1–0.5% Tween 81 into dairy mixes or dressings. Stir at 150 rpm at 25–30°C; avoid overheating (>80°C) to keep stability.
4、For Agriculture/Industry
Dilute to 0.2–1% concentration with water/pesticide or cleaning solutions. Stir well (100–200 rpm) before use; apply via standard sprayers/cleaning tools.
FAQ
1.Q: Can Tween 81 affect product color or odor?
A: No, Tween 81 is colorless and odorless. It won't alter the color or add any unwanted smell to your formulations, maintaining product integrity.
2.Q: How to store Tween 81 properly?
A: Store it in a cool, dry place, away from direct sunlight and heat sources. Temperatures between 15 - 25°C are ideal. This ensures its stability and extends shelf life.
3.Q: Is Tween 81 safe for sensitive skin in cosmetics?
A: Generally yes. Tween 81 has low irritancy. But for extra-sensitive skin, patch - test first. Its mild nature makes it suitable for most cosmetic applications.
4.Q: Can Tween 81 be used in high - temperature food processing?
A: Caution is needed. Avoid over 80°C as it may reduce stability. In baking or cooking, add it at appropriate stages to retain its emulsifying power.
