Acides gras de tall oil

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Tall oil fatty acid (TOFA) is the fatty-acid cut distilled from crude tall oil, the by-product of kraft pulping of pine wood. It is a FREE fatty acid, not a triglyceride: it neutralises lye directly, one hydroxide per carboxyl group, with no glycerol set free, so its saponification value is essentially its acid value. The figures here are Arizona Chemical's own product data sheet for SYLFAT FA2 Tall Oil Fatty Acid, revision 12/2012 (a US grade, shipping point Panama City, Florida; Arizona Chemical is now part of Kraton, which still sells SYLFAT FA2). Specifications: colour Gardner 1963 4 max (typical 3+); acid value 195-205 mg KOH/g (typical 197); rosin acids 1.0 % max. Typical analysis: saponification value 197; iodine value (Wijs) 130; titer 5 C (41 F); unsaponifiables 2.2 %; rosin acids 0.8 %; fatty acids total 97.0 %; moisture <0.1 %; ash <0.01 %. Fatty acids composition: saturated 2 %, oleic 50 %, linoleic nonconjugated 37 %, linoleic conjugated 7 %, other fatty acids 4 %. Those five figures add up to 100, so they are percent of total fatty acids and are recorded as such; the rosin acids and unsaponifiables sit outside that 100. Mapped: oleic 50 and nonconjugated linoleic 37, both typical values. Not mapped: conjugated linoleic acid 7 % (no schema key); saturated acids 2 % (the sheet does not split them into palmitic and stearic); other fatty acids 4 % (the sheet does not say what they are). That is why the profile sums to 87. The 0.8 % rosin acids are the diterpene resin acids of rosin.json; they take lye too and are inside the saponification value, but they are not fatty acids. Cross-checks: the sheet's previous revision (09/2010, archived June 2012) prints the same typical analysis and the same composition (acid value 197, saponification value 197, iodine value 130, titer 5 C, unsaponifiables 2.2, rosin acids 0.8, fatty acids total 97.0; 2 / 50 / 37 / 7 / 4) and differs only in printing the acid-value specification as 195 min. On the arithmetic, which is arithmetic and not a measurement: a free acid of the mapped composition has a mean molar mass of 281.6 and would neutralise 56106 / 281.6 = 199.2 mg KOH/g; the published 197 is 1.1 % lower, which is the direction 2.2 % unsaponifiable matter and 0.8 % of heavier resin acids should move it. The grade today: Kraton's current SYLFAT FA2 product data sheet (3 September 2025) prints acid number 195-205 mg KOH/g (typical 196), colour Gardner 4 maximum (typical 3), rosin acids 1 maximum (typical 0.8), and typical unsaponifiables 1.3 % and iodine number 125, but no fatty-acid composition and no saponification number; the four-grade table in Kraton's Oleochemical and Rosin Product Guide (2026) gives SYLFAT FA2 acid value 196, free rosin acids 0.9 %, unsaps 1.3 %, iodine value 125. The record keeps the 2012 sheet's figures together because they describe one material; a drum bought now should run a few units lower in iodine value and a little lower in unsaponifiables. Where the pine grew matters, and this record is the US type. Kraton's guide says its European, particularly Scandinavian, grades SYLFAT 2 and SYLFAT 2LT have more double bonds (higher iodine value) than grades of origin closer to the equator such as SYLFAT FA1 and FA2, and prints iodine values 151 and 154 against 125 and 125. Arizona Chemical's SYLFAT 2 sheet (revision July 2009, Almere) shows what that means: saturated fatty acids 3, oleic acid 29, linoleic acid and other polyunsaturated acids 57 non-conjugated and 7 conjugated, free fatty acids 96, free rosin acids 1.8 (max 2.1), unsaponifiables 2.0 (max 2.5), acid value 194 (min 193), saponification value 196, iodine value (Wijs) 155. Those composition figures add up to 96, the free-fatty-acid content, so they are percent of the product rather than of the fatty acids, and the 57 lumps linoleic acid together with the other non-conjugated polyunsaturated acids of pine; neither can be put in this schema without arithmetic, so they are given for comparison only. A Scandinavian TOFA is much less oleic and much more polyunsaturated than this record, which makes a softer soap that oxidises sooner, but its lye demand is the same to a unit or two: Kraton's current SYLFAT 2 sheet (3 September 2025) prints saponification number 197 and iodine number 152, and Forchem's FOR2 from Rauma, Finland (PDS FOR2 007, April 2026) prints saponification number 198, iodine value (Wijs) 140, acid value 195 (min. 193), free rosin acids 1.9 % (max. 2.1) and unsaponifiables 1.8 % (max. 2). Arizona Chemical's higher-rosin US grade SYLFAT FA1 (revision 09/2010) sits between: linoleic nonconjugated 34, linoleic conjugated 9, oleic 44, saturated 5, other fatty acids 8, rosin acids 4.3 % (max 5.0), unsaponifiables 3.4 %, saponification value 197, iodine value 131; the same sheet calls it particularly good in the manufacture of soaps. Checked and not used: Kraton's current SYLFAT sheets and Forchem's FOR2, FOR2X and FOR5 sheets print no fatty-acid composition; Ingevity's XTOL 3030 page offers its data sheet only through a request form, and ingevity.com returned 404 for XTOL 100, 101, 300, 304 and ALTAPYNE L1; Synthomer's PAMOLYN 150, 200 and 240 are oleic- or linoleic-enriched products made from tall oil fatty acid rather than plain TOFA (PAMOLYN 150 is 77 % oleic acid, 200 is sold as a high-purity linoleic acid and 240 as a linoleic acid-rich blend); a Pamak 4 sheet found on a distributor's site was not used because it is the distributor's document. Titer (5 C) is the solidification point of the fatty acids, not a melting point, so meltingPointC is null; TOFA is a liquid at room temperature. No source consulted prints an INCI name; the INCI name, CAS and EC numbers are CosIng's entry for Tall Oil Acid ('Fatty acids, tall-oil'), and the salt names are its entries for Sodium Tallate and Potassium Tallate. In soap, TOFA behaves as a liquid, mostly C18 unsaturated fatty acid: the soap is soft, the conjugated and polyunsaturated acids oxidise, and the small resin-acid share adds some tack.

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