Patent GB-844620-A (GB)
Title: Improvements in the preparation of condensation products from fatty acid anhydrides
Inventor: MIKUSCH-BUCHBERG JOHANNES DONA
IPC: C09F7/00
Filed: 1955-10-07
Abstract: A process for preparing condensation products comprises heating anhydrides of fatty acids as defined below at temperatures of 180 to 300 DEG C. in the presence of catalysts which are oxygen-containing compounds of boron, water liberated in the reaction being p continually removed from the reaction zone, the reaction being continued at least until the products contain substantial proportions (not less than 20% of their weight) of unsaponifiable matter of mean molecular weight not less than three times that of the fatty acid corresponding to the anhydride initially present. By "fatty acid" is means an acid of the formula RCOOH wherein R is an unsubstituted hydrocarbon chain radical containing a methylene group by which it is attached directly to the carboxyl group and containing at least 5 carbon atoms.  Fatty acid anhydrides specified include those derived from groundnut and linseed oil fatty acids linoleic and linolenic acids and the unsaturated acids occurring in marine oils e.g. herring, whale, pilchard and sardine oils and saturated acids such as caprylic, capric, lauric and stearic acids.  Aliphatic ketones of the formula RCOR1, where R and R1 have the meaning given for R above and fatty acids may be employed in admixture with the anhydrides as starting materials.  Minor proportions of glyceride oils, mono-, di- and triglycerides or resin acids may also be present in the starting material.  Boron containing compounds specified for use as catalysts include boric acid and its derivatives and boric oxide, boric acid salts of volatile bases e.g. ammonium borate, esters of boric acid, e.g. boric acid trimethyl and triethyl esters, boric acid mannitol ester and the mixed anhydrides of boric acid and acetic or higher fatty acids e.g. obtained from groundnut oil.  The catalyst may be supported on a suitable carrier e.g. an oxide of silicon, kieselgular, diatomite or silica gel.  The catalyst may be dissolved in or suspended in water, the carrier material added and the mixture dried.  The unsaponifiable matter of the condensation products has a molecular structure which contains at least three hydrocarbon chains derived from the anhydride treated (on the mixture of anhydride with fatty acid and/or ketone).  The preferred products are those in which the hydrocarbon chains are those of unsaturated fatty acids derived from fatty oils or are shorter than the chains of unsaturated acids derived from fatty oils by the loss of one carbon atom in the condensation reaction.  The products have drying properties and may be mixed with the usual siccatives.  In examples: condensation products are prepared from ground nut fatty acid anhydride (1) groundnut fatty acid anhydride and linseed oil fatty acid (2) and groundnut fatty acid ketone and groundnut fatty acid anhydride (3). The products may be used as drying substances in paints (see Group III).ALSO:Drying substances are prepared by heating anhydrides of fatty acids containing at least 5 carbon atoms optionally with fatty acids and/or ketones in the presence of an oxygen-containing compound of boron until the products contain substantial proportions of unsaponifiable matter (see Group IV(b)) and may be mixed with the usual siccatives based on cobalt, lead or manganese and may be diluted with turpentine, mineral spirits or other volatile solvents. Condensation products are prepared from groundnut fatty acid anhydride and mixtures of groundnut fatty acid anhydride and linseed oil fatty acid respectively and mixed with lead and manganese naphthenates to obtain film forming compositions.