Cashew Nut Shell Liquid (CNSL) is a dark, viscous liquid obtained from the honeycomb structure of cashew nut shells during processing. While the global cashew industry is widely known for edible kernels, CNSL is a lesser-known but highly valuable byproduct used extensively in industrial manufacturing.
🔬 What is CNSL?
CNSL is a natural phenolic liquid that contains a blend of:
- Anacardic acid (60–70%) – offers acid reactivity and anti-corrosion properties
- Cardol (15–20%) – contributes to polymer flexibility
- Cardanol (5–10%) – enhances thermal and chemical resistance
- Other trace alkenyl phenols
This unique chemical composition makes CNSL an ideal alternative to petroleum-based phenols in multiple industrial formulations.
🧪 Physical & Chemical Properties
- Appearance: Dark brown viscous liquid
- Specific gravity: ~0.95–0.98 at 30°C
- Acid value: 150–200 mg KOH/g
- Solubility: Soluble in alcohols, esters, and ketones
- Stability: Excellent resistance to heat and oxidation
CNSL can undergo polymerization, alkylation, and condensation reactions—offering high adaptability in resin synthesis and additive formulations.
🏭 Applications of CNSL Across Industries
- Automotive & Friction Materials Used in brake linings, clutch facings, and friction dust due to its heat resistance and binding properties.
- Paints & Coatings Ideal for marine coatings, anti-corrosive primers, and epoxy resins.
- Adhesives & Sealants Used as a reactive phenolic resin base in construction, flooring, and heavy-duty adhesives.
- Rubber & Plastics Improves flexibility and performance of vulcanized rubber and thermosetting plastics.
- Electronics & Insulation Applied in laminates, insulating varnishes, and circuit board compounds.
🌍 CNSL’s Green Credentials
- Bio-based & renewable
- Derived from agricultural waste (cashew shells)
- Lower carbon footprint vs fossil-based alternatives
- Supports sustainable industrial chemistry
📦 Commercial Supply
Vietnam is one of the world’s leading cashew processors, and CNSL is increasingly available in bulk industrial packaging. Suppliers like SVC Cashew offer:
- Crude or filtered CNSL
- Export packaging in 200L drums or 1000L IBC tanks
- Full documentation: COA, MSDS, and OEM/private-label options