Sebacic acid is a ten-carbon dicarboxylic acid made from castor oil. It is bought by makers of polyamides, plasticisers, synthetic lubricants, greases, polyester resins, corrosion inhibitors and cosmetic esters.
It is made by heating castor oil or ricinoleic acid with caustic soda at high temperature. The molecule splits into sodium sebacate and 2-octanol. The sebacate is then acidified, crystallised and dried into a white powder or flake.
Who buys it
- Engineering plastics makers, who use it for polyamide 610 and polyamide 1010 in tubing, brush filaments and fuel lines.
- Plasticiser makers, who turn it into esters such as dibutyl and dioctyl sebacate for low-temperature PVC and rubber.
- Lubricant makers, who use sebacate esters as base oils for jet engine and other high-performance lubricants.
- Grease makers, who use it in lithium complex greases.
- Coating, adhesive and polyurethane makers, who use it in polyester polyols and resins.
- Cosmetic and personal care ingredient makers, who use its esters as emollients.
- Makers of corrosion inhibitors for coolants and metalworking fluids.
Grades and what matters
Polymer grade needs high purity and low colour, because impurities affect polymerisation and the colour of the final polymer. Plasticiser and lubricant grades can tolerate slightly more. Ask what purity, moisture, ash, colour and iron content the plant guarantees for each grade.
Production needs large volumes of caustic soda and creates a salt-rich effluent. That makes it an environmentally sensitive process. Ask how the plant handles its effluent and whether its consent to operate is current. Our guide on what a factory audit should contain covers this.
Where it comes from and what to specify
India and China are the main producers. Indian plants sit close to the castor crop in Gujarat, which helps feedstock supply. Read why India is the main supplier of castor derivatives for the background.
A sebacic acid specification usually sets limits for the following. Agree the test method for each one, and ask for actual results on every certificate of analysis:
- Purity or assay, usually by titration or gas chromatography.
- Moisture, because the powder can pick up water in storage.
- Ash and iron content, which come from the process and equipment.
- Colour, often measured on a solution or a melt.
- Melting point range, which narrows as purity rises.
- Particle size, if you dose or dissolve the powder in a particular way.
Buying from a new plant
Polymer and lubricant buyers usually qualify a new sebacic acid source slowly. Expect to test a laboratory sample first, then a trial lot in your own process, before regular orders. Ask the plant for certificates from several recent lots so you can see how much purity and colour vary.
Ask also how the product is packed. Sebacic acid usually ships in lined bags, and moisture pick-up or caking in transit can cause problems at your plant. A pre-shipment check of bags and a lot-by-lot certificate are worth agreeing from the start.
Next step
We can find sebacic acid producers, test samples against your grade and supervise each shipment. Book a free sourcing review to start.