US2405380A - Ijnitfd statfs patfnt offipf - Google Patents

Description

Patented Aug. 6, 1946 UNITED s'rrss I 7 2,405,380 CONJUGATED FATTY roman COMPOUNDS Amos Turk, Mount Lebanon, Pa., and Paul D. Boone, Washington, D. C.

No Drawing. Application October 9, 1944, Serial No. 557,930 7 10 Claims.

It is recognized that the rapidity of drying China-wood oil and oiticica oil is due to triply unsaturated and conjugated eleostearic and licanic acids respectively. It is accordingly an object of this invention to produce oils similar in structure to these aforesaid oils. Moreover it is an object of this invention to produce oils which have similar properties to these aforesaid oils.

It is an additional object of this invention to provide means for controlling the reaction of shifting double bonds in fatty polyene compounds so that the reaction may go only partially to completion, so that only a desired fraction of the starting material is caused to isomerize to attain conjugation. In this way the extent of change in properties which accompany conjugation may be controlled. However there should be at least fifteen and preferably 40% or more conjugation calculated from the increase of refractive index in the isomerized polyene liquid to merit replacement in coating compositions of tung-, oiticica-, or dehydrated castor oils. In fact, it is with those oils wherein their conjugation exceeds 40% and approaches 80% that this is fully realized.

The starting materials used in this invention, that is to say, the materials with non-conjugated or isolated double bonds, are diene or polyene carboxylic acids and their esters, whether obtain d synthetically or from natural sources, and also any other unconjugated dienic or polyenic compounds contained in or derived from naturally occurring oils and fatty substances, whose acyl nucleus has twelve or more carbon atoms. It is preferred that the acyl nucleus contain sixteen or more carbon atoms. These materials may be either individual compounds in a state of high purity, or else mixtures which contain various unsaturated polyenes, such as the mixtures found in nature. Such unsaturated compounds are in fact abundantly found in natural substances, and make up important constituents of many animal and vegetable oils. These oil include such materials derived from nature as linseed oil, soy bean oil, Perilla' oil, sunflower oil, safiiower and various suitable marine oils such as sardine, menhaden, pilchard and whale oils. Various members of the semi-drying oil class per e or freed in part or in toto from saturates or oleates or both but not numerically below 120 iodine number may be used. The fatty acids from unsaturated oils zeta-405.6)

either without fractionating, or freed from satu rated acids or oleic acid or both can be used also, or equivalent artificial acids. The amides of said unsaturated acids such as of linoleic-, linolenicand clupanodonic acids may be employed.

When these non-conjugated unsaturated materials are treated by the methods of this invention so that the double bonds shift to produce conjugation, important changes in properties occur. These resulting products are compounds containing conjugated system of double bonds, and the new properties which are imparted to the products or their derivativesinclude the property of entering into the diene reaction or of increasing the diene number, and the property of increasing the index of refraction and of exalting the molecular refraction.

The process of this invention which causes shifting of the double bonds of the unconjugated fatty polyene compounds into conjugated positions broadly consists in heating these liquid compounds in the presence of a magnesium silicate until the degre of conjugation is at least 15% (calculated from the increase of refractive index) and much preferably approximately 40-80%. These compounds may be vaporized, as

by an inert gas, and heated in the vapor state in the presence of a magnesium silicate.

The amount of the catalyst of this invention may vary from about 0.5% to about 80% of the amount of liquid fatty polyene treated, but proportions of about 2% to about 20% of the amount of the liquid are best. The temperature range is substantially from 200 C. to 350 C.

This invention also consists in heating such unconjugated or partially conjugated fatty polyene liquids in the presence of mixtures of such aforesaid specified silicates with other adjuncts. Such adjuncts may be a dihydric or trihydric phenol or naphthol derivative; decolorizing carbons, i. e. activated carbons; metallic oxides such as alumina, chromium oxide, thoria; and various other solid porous or cellular constituents or carriers such as silica and pumice. In no case does this invention cover heating fatty polyene liquids with natural silicates, such as fullers earth, which have traces of a magnesium silicate according to the analysis.

In order to exclude oxygen and thus avoid any oxidative degeneration which might result, it is advisable to carry out the reaction in the presence of an inert gas such as carbon dioxide or nitrogen.

The process may be executed in batch, intermittent or in a continuous manner. It is part cularly well adapted to a continuous mode of operation. By one such mode, the unsaturated fatty oil or unsaturated higher carboxylic acids are passed through a reaction chamber packed with catalyst maintained at the desired temperature. In general, when lower temperatures are employed, lower space velocities are more advantageous and at higher temperatures much higher space velocities are employed. When operating in a continuous mode, the isomerized fatty oil or fatty acids from the heated region within the tube can be immediately cooled in its flow to arrest any undesirable changes such as polymerization. Such can be by a cool inert gas or by filming, etc. Certain portions of the apparatus must be constructed of corrosion-resistant materials to prevent rapid deterioration thereof from the action of any acid compounds present. The reaction vessel and/ or tubes should be constructed of or lined with non-ferrous materials such as glass, ceramic substances, aluminum or corrosion resistant alloys such as stainless steel.

The apparatus employed may be a bomb-shaker in which the bomb is placed. Such an apparatus provided with a heating jacket heats the bomb in which the reaction is taking place and agitates the mixture well. Or the apparatus may consist of a single pressure reactor equipped with a mechanical agitator, such as a motor driven propeller, jets of restricted internal diameter, turbomixer, and the like. Or a rotating autoclave can be used. Vigorous agitation or at least thorough agitation should be employed. The catalysts can be added as a slurry in the same polyene liquid to be treated. The particle size of the catalyst can be 8 to 20 mesh and may be even more finely divided such as 200 mesh; the size is not critical. The oily liquid should be freed of oxygen by treatment with an inert gas such as N2 or by other modes.

The progress of the degree of conjugation can be followed by taking samples from the batch and determining the gelation time by standard methods, the refractive index and the diene number. When the desired properties are reached, the heating is stopped. The treated material in liquid form is quickly cooled preferably.

The following examples illustrate the invention but in no sense are limitations thereon.

Example 1 100 parts of linseed oil fatty acids were mixed with parts of powdered magnesium silicate (product of Pacific Silicate Co. designated #16). The mixture in the reaction vessel was evacuated several times and rinsed with nitrogen, so as to insure an inert atmosphere. The mixture was then heated to 250 C. for 4 hours at atmospheric pressure, all the time being protected from the action of air by the nitrogen present. The mixture was cooled quickly, filtered and the liquid analyzed. There was a change of ra from 1.4700 to 1.4779 (+0.0079) and the molecular refraction from 83.64 to 84.83 (+1.19).

Example 2 100 parts of sardine oil are mixed with 6.5 parts of finely powdered magnesium sesquisilicate. The mixture in the reaction vessel is evacuated several times, and rinsed with nitrogen so as to insure an inert atmosphere. The mixture is then heated to 250 C. for 4 /2 hours at atmospheric pressure, all the time being protected from the action of air by the inert nitrogen present. Mechanical agitation (150 R. P. M.) may be used. 7

At the end of the reaction period, the mixture is cooled quickly to about 70 C. and filtered.

The refractive index increase and diene number prove that the oil has undergone conjugation.

Example 3 The same procedure was carried out with trisilicate instead of the tetrasilicate, as indicated in Example 1 supra.

Example 4 The unsaturated fatty acids from Perilla oil, are vaporized by an inert gas as convective medium and passed through the solid magnesium silicate catalyst in a stainless tube. A tube suitable for the purpose is 1 x 20". The jacketed medium is maintained at 265 C. The vapors are condensed as they leave the tube. One-half of the condensate is esterified with glycerine and the other half with pentaerythritol.

The products of our invention are fast-bodying and quick setting, hence suitable for varnishes and enamel. Their varnishes dry fast and the films therefrom are hard and tack-free; they are excellent water and good alkali resistance. The conjugated linseed oil dries faster than either polymerized or unpolymerized linseed oil.

This application is a continuation-in-part of Serial No. 501,608 filed September 9, 1943. The term fatty acid as used herein is the same as employed industrially in the fatty oil industry and designates those carboxylic acids of at least 12 carbon atoms.

As many apparently widely different embodiments of this invention may be made without departing from the spiirt and scope thereof, it is to be understood that this invention is not to be limited to the specific embodiments thereof except as defined in the following claims.

We claim:

1. In the process of producing conjugation, the step of heating a liquid containing a non-conjugated polyene compound which has an acyl nucleus of at least 12 carbon atoms, with a solid magnesium silicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

2. In the process of producing njugation, the step of heating a liquid containing a nonconjugated polyene compound which has an acyl nucleus of at least 12 carbon atoms, with a solid magnesium silicate, at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 40% above the initial liquid, calculated on the basis of the increase of refractive index.

3. In the process of producing conjugated fatty polyene compound, the steps of passing a substantially unconjugated unsaturated polyenic fatty substance having an acyl nucleus of at least 12 carbon atoms in a vapor state over a solid magnesium silicate at a temperature above 200 C. but below the decomposition range, then cooling the vapors to a liquid.

4. In the process of producing conjugation, the step of heating a, liquid containing a nonconjugated polyene compound which has an acyl nucleus of at least 12 carbon atoms, with magnesium sesquisilicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

5. In the process of producing conjugation, the step of heating a liquid containing a non-conjugated polyene compound which has an acyl nucleus of at least 12 carbon atoms, with magnesium trisilicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

6. In the process of producing conjugation, the step of heating a liquid containing non-conjugated polyene carboxylic acids of at least 12 carbon atoms with a solid magnesium silicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

7. In the process of producing conjugation, the step of heating a liquid contain'ing non-conjugated polyene ester of a carboxylic acid, the acyl nucleus of which contains at least 12 carbon atoms, with a solid magnesium silicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

8. In the process of producing conjugation, the

step of heating a liquid containing non-conjugated polyene ester of a carboxylic acid, the acyl nucleus of which contains at least 12 carbon atoms, with a solid magnesium sesquisilicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% above the initial liquid, calculated on the basis of the increase of refractive index.

9. In the process of producing conjugation, the step of heating a liquid containing non-conjugated polyene ester of a carboxylic acid, the acyl nucleus of which contains at least 12 carbon atoms, with a solid magnesium trisilicate at a temperature not below substantially 200 C. until the resulting liquid has a conjugation of at least substantially 15% calculated on the basis of the increase of refractive index.

10. In the process of producing conjugation in fatty polyene carboxylic acid, the steps of passing a polyene carboxylic acid which has at least 12 carbon atoms in a vapor state over a solid magnesium silicate at a temperature above 200 C. but below the decomposition range, then cool ing the vapors to a liquid.

AMOS TURK. PAUL D. BOONE.