Chemical Properties
Dehydrated Castor oil fatty acid commonly known as DCOFA is a high diene fatty acid based on Castor oil. Three types are offered depending on the conjugation (low, medium and high). DCOFA is liquid at room temperature, having a water-white to pale yellow colour.<br />
Standard specifications low medium high
refractive index at 25°C 1,473-1,477 1,473-1,477 1,473-1,477
specific gravity at 25°C 0,903-0,905 0,903-0,905 0,903-0,905
colour Regular Gardner max. 2 max. 2 max. 2
colour Special Gardner max. 1 max. 1 max. 1
acid value 195-205 195-205 195-205
iodine value min. 130 min. 130 min. 130
iodine value 160-175 160-175 160-175
saponification value 198-208 198-208 198-208
hydroxyl value max. 5 max. 5 max. 5
lower components % 1,2-1,4% 1,2-1,4% 1,2-1,4%
palmitic acid % 1,3-1,5% 1,3-1,5% 1,3-1,5%
stearic acid % 1,8-2% 1,8-2% 1,8-2%
oleic acid % 4-6% 4-6% 4-6%
linoleic acid (non-conjugated) % 45-55% 30-45% 25-30%
linoleic acid (conjugated) % 35-45% 45-60% 60-66%
total Linoleic acid % 88-95% 88-95% 88-95%
linolenic acid % max. 0,5% max. 0,5% max. 0,5%
conjugation by UV spectrometer (factor 0,91) min. 30 min. 40 min. 50
Uses
Dehydrated castor oil fatty acid based alkyd resins and polyamides make up superior constituent in numerous paint and printing inks formulations. Styrenated epoxy esters of these fatty acids are used in prime quality automotive paints.
DCOFA is also used in the manufacture of high solid alkyds, acrylic and epoxy ester resins, which are useful for interior and exterior can coatings, appliance finishes, automotive topcoats, primers, coil coatings, tube coatings, marine finishes, overprint varnishes and high-speed printing inks.
Furthermore DCOFA can be used as chemical intermediate because of their conjugate dienes structure.
