Methyl 12-Hydroxy Stearate (M12HSA): Technical Properties and Industrial Applications

1. Technical Overview

Methyl 12-Hydroxy Stearate (Methyl 12-HSA or M12HSA) is a methyl ester derived from the esterification of 12-Hydroxy Stearic Acid or the transesterification of Hydrogenated Castor Oil.¹ It is a waxy, white solid at room temperature that melts into a low-viscosity liquid.² In industrial R&D, M12HSA is highly valued as a high-purity chemical intermediate. Compared to 12-HSA acid, the methyl ester version offers a lower melting point and superior solubility in organic phases, making it an ideal choice for the production of high-performance lithium complex greases, high-end cosmetics, and as a specialized lubricant in plastic processing.

2. Chemical Structure & Composition

M12HSA is the methyl ester of 12-hydroxystearic acid (³$C_{19}H_{38}O_3$).⁴ Its structure consists of a long 18-carbon saturated chain with a hydroxyl group at the C12 position and a methoxy group at the carboxyl end.

• Methyl 12-Hydroxystearate Content: Minimum 85-88%.

• Saturated Esters: Balanced distribution of methyl stearate and methyl palmitate.

• Functional Sites: Retains the secondary hydroxyl group for further chemical modifications.

The esterification of the carboxyl group reduces the molecular polarity compared to the free acid, allowing for better dispersion in non-polar hydrocarbon systems.

3. Physical & Chemical Properties

• Appearance: White to off-white waxy solid (flakes or blocks).⁵

• Melting Point: 48°C to 52°C (significantly lower than the 75°C of 12-HSA).

• Solubility: Excellent solubility in alcohols, esters, and aromatic hydrocarbons when heated. Insoluble in water.

• Acid Value: Very low (<5.0 mg KOH/g), indicating a near-complete conversion of the acid to the ester.

• Iodine Value: Low (<5.0), ensuring high oxidative and thermal stability.

4. Reaction Chemistry

The methyl ester group provides a strategic advantage in chemical processing:

1. Transesterification: Reacts efficiently with other alcohols or polyols to create specialized lubricants and emollients.

2. Saponification (Grease Cooking): In the production of lithium greases, M12HSA reacts with lithium hydroxide. The release of methanol (instead of water) during this reaction allows for faster “de-watering” and more efficient soap fiber formation.

3. Hydroxyl Modification: The C12 hydroxyl group can be further reacted with isocyanates to produce specialized polyurethane additives.

5. When to Use vs. When NOT to Use

Use Methyl 12HSA when:

• Manufacturing high-performance lubricants where a low-acid, high-purity intermediate is required.

• Formulating cosmetic “sticks” or creams that require a waxy component with a melting point near body temperature.

• Producing specialized plastic additives that require an ester-based internal lubricant.

Do NOT use Methyl 12HSA when:

• The process cannot accommodate the release of methanol (the byproduct of saponification).

• A high-viscosity “acid-thickened” system is required (use 12-HSA instead).

• The application requires a liquid at room temperature (use Ricinoleic acid or Castor Oil instead).

6. Compatibility Profile

M12HSA exhibits excellent compatibility with:

• Waxes: Paraffin, Microcrystalline, and Carnauba waxes.

• Oils: Mineral oils, PAO, and synthetic esters.

• Polymers: PVC, Polystyrene, and various elastomers.

7. Manufacturing Process (Product Focus)

The production of M12HSA at Nova Industries involves:

1. Esterification: Reacting high-purity 12-HSA with methanol in the presence of an acid catalyst.⁶

2. Refining: Multi-stage washing to remove residual catalyst and unreacted methanol.

3. Vacuum Distillation: Advanced distillation ensures the removal of heavy ends and color-causing impurities.

4. Solidification: The molten ester is cooled and flaked for easy handling and dosing.

8. Technical Specifications Table

Parameter	Specification (Methyl 12-HSA)
Appearance	White to Off-White Waxy Flakes
Melting Point (°C)	48 – 52°C
Acid Value (mg KOH/g)	5.0 Max
Iodine Value (g I2/100g)	5.0 Max
Saponification Value	175 – 185
Hydroxyl Value	150 – 160
Color (Gardner)	2.0 Max

9. Quality Grade Analysis

Nova Industries monitors the Acid Value and Hydroxyl Value as critical quality markers. A high acid value indicates incomplete esterification, which can interfere with the performance of M12HSA in sensitive cosmetic formulations or high-end lubricants. Our vacuum distillation process ensures a consistently low acid value and a very light color.

10. Impact of Impurities

• Residual Methanol: If present, it poses a safety risk due to a lowered flash point and can cause odor issues.

• Unreacted 12-HSA: Can cause the melting point to be inconsistent and affect the solubility of the product in oil phases.

11. Industry-Wise Application 1: Lubricant Greases

M12HSA is a premium alternative to 12-HSA for Lithium Complex Greases. Because it is a methyl ester, the saponification reaction is more controlled and the resulting soap fibers are often finer, leading to greases with improved mechanical stability and better low-temperature performance.

12. Industry-Wise Application 2: Cosmetics & Personal Care

In lipsticks, deodorants, and skin creams, M12HSA acts as an emollient and structural agent. Its melting point (near 50°C) allows it to provide a smooth “glide” upon application while maintaining the stick’s integrity at room temperature.

13. Industry-Wise Application 3: Plastics & Polymers

Used as an internal lubricant and mold release agent for engineering plastics. It improves the surface gloss and reduces the friction of the polymer melt during processing.

14. Industry-Wise Application 4: Chemical Intermediates

A building block for the synthesis of various specialized surfactants, amides, and esters used in the textile and leather industries.

15. Formulation Guide

• Grease Cooking: When reacting M12HSA with Lithium Hydroxide, ensure the reaction vessel is equipped with a condenser to safely capture and recover the released methanol.

• Cosmetic Blending: Melt M12HSA with other waxes and oils at ~60°C to ensure a homogenous phase before cooling.

16. Sustainability Data

Methyl 12-HSA is a bio-based product derived from renewable castor oil.⁷ It offers a high degree of biodegradability and helps manufacturers increase the renewable carbon content of their final products.

17. Packaging & Logistics (Technical)

• Standard: 25kg Paper/HDPE Bags with moisture-proof liners.

• Bulk: 500kg or 1000kg Jumbo Bags.

• Logistics: Classified as non-hazardous for transport. Due to its 50°C melting point, it should be kept away from high-heat areas to prevent “caking.”

18. Storage Science

M12HSA should be stored in a cool, dry environment.⁸ While stable, it can undergo minor hydrolysis if exposed to moisture for extended periods, which would increase the acid value. Stainless steel or epoxy-lined containers are recommended for handling the molten material.

19. Troubleshooting Guide

• Problem: Clumping of flakes in the bag. Solution: Store in a temperature-controlled warehouse below 35°C; ensure bags are not stacked too high.

• Problem: Inconsistent grease consistency. Solution: Verify the saponification value of the M12HSA batch to ensure the alkali dosage is correct.

20. Regulatory Compliance

Our M12HSA is REACH Compliant and produced under strict ISO-aware manufacturing standards, making it suitable for global export to highly regulated markets.

21. Safety (SDS Summary)

• Handling: Wear gloves and safety glasses.¹⁰ Avoid inhaling dust during flake handling.

• Fire: Use CO2, dry chemical, or foam extinguishers.

• Methanol Safety: If used in a closed reactor, ensure the system is grounded to prevent static discharge during methanol release.

22. Sample Validation Process

For procurement validation, we recommend testing the Melting Point and Acid Value. A lab-scale solubility test in the customer’s specific base oil is the most effective way to confirm compatibility.

23. Commercial Efficiency

By using high-purity M12HSA from Nova Industries, manufacturers can optimize their production cycles. The low acid value and high hydroxyl consistency ensure that batch-to-batch adjustments are minimized, leading to more predictable manufacturing costs.

24. Technical FAQs

1. What is the benefit of using M12HSA over 12-HSA? M12HSA has a lower melting point and better solubility in oils, which can simplify the manufacturing process for certain greases and cosmetics.¹¹

2. Is M12HSA biodegradable? Yes, it is derived from vegetable oil and is inherently biodegradable.

3. Can it be used in food-contact applications? In many regions, castor derivatives are approved for indirect food contact; please check specific local regulations.

25. Contact CTA

For Technical Data Sheets (TDS), customized specifications, or to request a sample, please contact our export department: export@novaind.in