Patent GB-428864-A (GB)
Title: Improved drying oils and their application
Filed: 1933-11-15
Abstract: Esters and ester-condensation in products which serve as quick-drying stand oils are obtained by polymerizing fatty acids of drying or semi-drying oils or the alkyl esters of such acids, distilling off all or part of the unpolymerized constituents, and converting the residue into esters of glycol, glycerol, or higher polyhydric alcohols such as penta-erythritol, mannitol, and quebrachitol, or mixtures thereof; colophony or other acid resins, or polycarboxylic acids or their anhydrides, or mixtures thereof may be present during the esterification.  To prevent gelation during the esterification process it is preferred to remove only part of the unpolymerized material at the distillation stage, or to add unpolymerized acids prior to esterification.  In examples: (1) 1000 kg. of linseed oil fatty acids are heated in carbon dioxide to 265--275 DEG  C. for 17--18 hrs., and 250 kg. of the product distilled off at 2--3 mm. pressure and 200--205 DEG  C.; 158 kg. of the still residue are heated with 16 kg. of glycerol to 205--210 DEG  C. for 5--6 hrs. (4) 34 kg. of glycerol and 113 kg. of colophony are stirred together at 245--270 DEG  C. under carbon dioxide for 3--5 hrs., and the product stirred at 220--230 DEG  C. under carbon dioxide for 12--14 hrs. with 226 kg. of the still residue of example 1.  (5) 222 kg. of the still residue of example 1, 162 kg. of linseed oil fatty acids, 162 kg. of phthalic anhydride, and 100 kg. of glycerol are heated to 240--245 DEG  C. for 3--4 hrs.  Specification 359,365 is referred to.ALSO:Stand oils which dry quickly and form hard, resistant, glossy films, are obtained by polymerizing fatty acids of drying or semi-drying oils or the alkyl esters of such acids, distilling off all or part of the unpolymerized constituents, and converting the residue into esters of glycol, glycerol, or higher polyhydric alcohols such as penta-erythritol, mannitol, and quebrachitol, or mixtures thereof; colophony or other acid resins, or polycarboxylic acids or their anhydrides, or mixtures thereof may be present during the esterification, whereby resinous mixed esters result. Polymerization is effected with but little oxidation by heating or by treatment with silent electric discharges; the alkyl esters may be polymerized and then saponified to produce the polymerized acids. Drying and semi-drying oils specified are linseed, tung, perilla, chia, octicica, soya bean, poppy seed, sunflower seed, hemp seed, safflower seed, rubber seed, cottonseed, candle nut, maize, wheat, croton, rape, menhaden, sardine, and herring oils.  To prevent gelatin during the esterification process it is preferred to remove only part of the unpolymerized material at the distillation stage, or to add unpolymerized acids prior to esterification.  In examples:--(1) 1000 kg. of linseed oil fatty acids are heated to 265--275 DEG  C. for 17--18 hrs. under a stream of carbon dioxide and 250 kg. of the product distilled off at 2--3 m.m. pressure and 200--205 DEG  C.; 158 kg. of the still residue is heated with 16 kg. of glycerol to 205--210 DEG  C. for 5--6 hrs.  A varnish is produced by mixing 50 kg. of the resulting pale yellow oil with mineral spirit of B.P. 165--210 DEG  C. and 0,05 gm. of cobalt as cobalt linoleate. (4) 34 kg. of glycerol and 113 kg. of colophony are stirred together at 245--270 DEG  C. under carbon dioxide for 3--5 hrs., and the product stirred at 220--230 DEG  C. under carbon dioxide for 12--14 hrs. with 226 kg. of the still residue of polymerized linseed oil fatty acids of Example 1.  (5) 222 kg. of the still residue of polymerized linseed oil fatty acids of Example 1, 162 kg. of linseed oil fatty acids, 162 kg. of phthalic anhydride, and 104 kg. of glycerol are stirred together at 240--245 DEG  C. for 3--4 hrs. under carbon dioxide; a viscous resinous mass results.  (8) Cottonseed oil is stirred for 20 hrs. at 285--295 DEG  C. in carbon dioxide, the polymerized oil is saponified by aqueous alcoholic caustic potash, and the fatty acids are precipitated by dilute mineral acid; 1,000 kg. of the crushed and dried acids are heated at 5--7 m.m. pressure until 250 kg. have distilled off, and 70 C. kg. of the residue are stirred in carbon dioxide with 70 kg. of glycerine for 8 hrs. at 220--225  DEG  C., and then for 1 hr. at 245--250 DEG  C. Specification 359,365 is referred to.