Dehydrated Castor Oil (DCO)
Manufactured by Nova Industries
Nova Industries manufactures premium-grade Dehydrated Castor Oil (DCO), a unique “drying oil” that bridges the performance gap between Linseed Oil and Tung Oil.
While raw castor oil is a non-drying oil suitable for lubrication, our specialized dehydration process transforms it into a highly reactive binder. By removing the hydroxyl group and creating a conjugated double bond system, we produce an oil that polymerizes rapidly upon exposure to air, forming tough, glossy, and non-yellowing films essential for the paint and resin industries.
1. The Manufacturing Process (Dehydration)
The conversion of Castor Oil to DCO is a precise chemical engineering feat performed at our facility.
- Reaction Conditions: Raw Castor Oil is heated to approximately 250°C under high vacuum in the presence of acidic catalysts (e.g., Sulfuric Acid or Activated Earths).
- Chemical Transformation: The reaction removes the hydroxyl group (-OH) from the 12th carbon and a hydrogen atom from the 11th or 13th carbon. This is eliminated as a water molecule ($H_2O$).
- Conjugation: This elimination creates a second double bond. Crucially, a significant portion of these new bonds are Conjugated Dienes (9,11-linoleic isomers).
- The Result: The oil changes from non-drying to a Drying Oil with reactivity similar to Tung Oil but without the risk of “frosting” or yellowing.1
2. Key Performance Advantages
DCO is celebrated in the coatings industry for specific properties that other drying oils cannot match.
- Non-Yellowing: Unlike Linseed Oil or Tung Oil, DCO films do not yellow over time, making them ideal for white enamels and clear varnishes.2
- Flexibility & Adhesion: The long fatty acid chains provide exceptional flexibility to the cured film, preventing cracking on flexible substrates.3
- Rapid Drying: The conjugated double bonds facilitate fast oxidative polymerization (drying).
3. Industrial Applications
Alkyd Resins & Surface Coatings
- Primary Binder: DCO is the premium choice for modifying medium-to-short oil alkyd resins. It imparts high gloss, excellent flow, and superior color retention to white appliances finishes (refrigerators, washing machines).
- Varnishes: Used in “Spar Varnishes” and marine coatings where water resistance and toughness are required.4
Inks & Epoxies
- Epoxy Esters: DCO fatty acids are reacted with epoxy resins to produce epoxy esters used in chemical-resistant primers and maintenance coatings.
- Printing Inks: Acts as a binder in lithographic and letterpress inks, ensuring sharp print quality and fast setting.5
Rubber Additives (Factice)
- DCO Factice: When vulcanized with sulfur, DCO forms “Factice,” a rubber additive used to improve the flow properties and ozone resistance of natural and synthetic rubbers.6
Plasticizers
- Epoxidized DCO: Can be used as a stabilizer/plasticizer in PVC compounds, offering potential replacement for Epoxidized Soybean Oil (ESO) in niche applications.
4. Technical Specifications (TDS)
Nova Industries offers standard monomeric DCO (G-Grade) and polymerized variants upon request.
| Parameter | Specification (Standard Grade) | Test Method |
| Product Name | Dehydrated Castor Oil (DCO) | — |
| CAS Number | 61789-45-5 | — |
| Appearance | Clear, Viscous Yellow Liquid | Visual |
| Viscosity (Gardner-Holdt) | G – J (approx. 1.6 – 2.5 Poise) | ASTM D1545 |
| Color (Gardner) | 6 Max | ISO 4630 |
| Acid Value | 5.0 Max | ISO 660 |
| Iodine Value | 125 Min | ISO 3961 |
| Hydroxyl Value | 25 Max (Indicates dehydration efficiency) | ISO 4326 |
| Saponification Value | 185 – 194 | ISO 3657 |
| Specific Gravity @ 30°C | 0.930 – 0.940 | — |
| Refractive Index @ 25°C | 1.480 – 1.482 | — |
Packaging & Handling
- Packaging: 200 Kg Steel Drums / 20 MT ISO Tanks.
- Storage: DCO is reactive. Containers must be kept tightly closed to prevent premature polymerization (skinning) caused by exposure to air. Store in a cool place.
For Resin Formulations & Bulk Supply:
Nova Industries
Website: https://novaind.in/