Modification of fatty oils
US 2298916 A
Description (OCR text may contain errors)
Patented Oct. 13, 1942 OFFICE MODIFICATION OF FATTY OILS rams Auer, East Orange, N. J.
No Drawing. Application January 8, 1942, Serial No. 428,083
28 Claims. (Cl. 280-}07) GENERAL FIELD OF INVENTION The invention relates to "modification of organic isocolloids," and to the modified products.
By "isocolloids" I mean organic colloidal substances containing mixtures of unsaturated carbon compounds. The dispersed phase and the dispersion medium of these colloidal systems are both of the same chemical composition but in a different physical state. Organic isocolloids are mixtures of chemically similar organic compounds wherein one or more of those compounds, serving as dispersed phase, are dispersed or dissolved in the others which serve as the dispersion medium of this isocolloid system. With such isocolloidal systems (or organic isocolloids) it is possible, by modification," to change the relative concentration of the dispersed phase and the dispersion medium. For instance, it is possible to increase the dispersed phase concentration, in which event the amount of the dispersion medium will be correspondingly reduced.
The colloidal transformation brought about in accordance with the invention apparently involves an alteration in the number, size or physical state of the colloid aggregations (micelles).
Briefly summarized, the processes according to my invention contemplate dispersion of a modifying agent in the organic isocolloid, and usually also the application of heat. In this way modification" is brought about and various characteristics and properties of the starting materials are altered, the nature and degree of alteration depending upon the treatment and also upon the nature of the isocolloid used as starting material.
Some of the more important effects of the colloidal transformations incident to modification are, for example, in the case of fattyoils, changes in drying characteristics, body, viscosity, melting point, elasticity, film strength, etc.
Other changes may also be brought about by treatment in accordance with my processes.
There are many types of organic isocolloids capable of treatment in accordance with the broad aspect of the invention, for instance, fatty oils, fatty acids and materials containing the same, i. e., glycerides of fatty acids, whether or not such glycerides also contain other acids; also resins, waxes, tars, pitches, etc.
The present invention is particularly concerned with modification of glycerides of fatty acids, such as fatty oils, examples of which are given hereinafter.
In accordance with the broad aspect of the invention, many diflerent materials and classes thereof may be employed as modifying agents. In general, these materials are electrolytes or polar compounds. The present application is directed to the use of inorganic acids as modifying agents for glycerides of fatty acids, such as fatty oils.
Various features of my improved processes are disclosed and claimed in copending applications, some of which are mentioned hereinafter. The subject matter claimed in the present application is also disclosed in my prior application Serial No. 318,650, filed February 12, 1940, of which the present application is a continuationin-part. It may further be noted that certain subject matter of the present application was also disclosed in my earlier applications including 359,425 (Patent No. 2,213,944) and 143,786 (Patent No. 2,189,772).
The STARTING liia'rasrar.
Tung oil Rapeseed oil Castor oil Walnut oil Linseed oil Pine seed oil Fish oil (train oils) Corn oil Poppyseed oil Olive oil The ease of transformation or modification, under equal conditions, decreases in the order given. That is, the first mentioned oils are most rapidly modified by my methods, while the oils at the end of the series are modified more slowly. However, it should be also mentioned that by the employment of suitable modifying agents in my methods, even the last mentioned oils (those at the end of this series) can be profoundly modified, as well as those oils appearing in the first of the series.
The foregoing listed, and other fatty oils may be classified as follows:
The liiobrrrmo Aoss'r As mentioi ed above, the present application is directed to the use of inorganic acids in association with esters of fatty acids, for instance, fatty oils. Both monobasic and polybasic acids may be used, the following list being given by way of example.
Hydrochloric Thiosulphuric Hydrobromic Nitric Hydroiodic Nitrous Sulphuric Borlc Chlorsuiphonic Phosphoric Sulphurous (HzSOaSOa) Hydrocyanio Hydrosulphuric (H28) Thiocyanic Hydrosulphurous In using various of the inorganic acids listed, it should be kept in mind that, because of difierent physical characteristics, the various acids must be handled in difierent ways.
Wherever they exist, the anhydrides may be used instead of the acids themselves.
In general, it may be said that I prefer to use sulphuric, chlorsulphonic, phosphoric and boric acids for the present purposes, especially sulphuric, for the reason that these acids may readily be handled at the relativehr high temperatures required for treatment. The action of chlorsuipnonic is similar to sulphuric, both of these acids being herein considered as polybasio acids.
Certain of the acids listed (hydrochloric, hydrobromic, hydroiodic, hydrosulphuric and hydrocyanic) are gaseous, although they may exist in aqueous solution, having a maximum saturation point. In the case of these acids, pressure, produced for example in an autoclave, is required, in order to prevent volatilization at the temperatures employed. On the other hand, certain acids of this group may alternatively be used in the gaseous state either by bubbling the gas through the material undergoing treatment or by blanketing the surface of the material being treated in which event no autoclave or other pressure treatment is necessary.
Hydrosulphurous and nitrous acids would be handled similarly to those mentioned Just above since the anhydride is gaseous and volatile-and at high temperatures requires pressure, although, as above. the anhydride may be used by bubbling through the material undergoing treatment. or by blanketing the surface of the material. v
Hydrosulphurous, nitrous and thiosulphuric acids exist only in very dilute solutions and in view of this characteristic, when employing these particular acids, I prefer to produce them in situ. The decomposition products of these acids may also be employed under certain circumstances.
Thiooyanic acid, although liquid, is relatively unstable and, therefore, son .ewhat diillcult to employ from the practical standpoint.
Nitric acid, being partly volatile at high temperatures and partly oxidizing may, under some circumstances, be used either with or without pressure, although this particular acid should not be selected in cases where oxidizing of the material under treatment would be pixlectionable.
The inorganic acids are especially useful in bodying and increasing the drying rate of fatty oils, such as linseed oil, soya bean oil and cmtor oil. This is advantageous in modifying non-drying and semi-drying fatty oils, as well as in treatment drying oils. The rate of bodying 0! fatty oils is also increased by the use of inorganic acids. I have found that thick oil-like products can be obtained from thin oils.
Tnaa'rsrszvr CONDITIONS The first step of the process is to mix the modifying agent with the organic isocolloid to be modified, and to produce an intimate admixture of the two materials. Most inorganic acids (or commercially available aqueous solutions thereof), being liquid, may b directly mixed with the oils by stirring. This may be done with the materials cold, that is, at room temperature. or may be done after heating (discussed hereinafter).
Aqueous solutions of gaseous inorganic acids may also be mixed merely by stirring, and with acids which are normally solids mixing may be effected by first dissolving the acids, or directly by fusing or melting.
Although many modifying agents are capable of use throughout a wide percentage range (for instanc from a fractional percentage up to about 30%), the inorganic acids should ordinarily be used in amounts from about .0l% to about 5% (based on the starting material), the preferred range being from .0l% to .9%.
The foregoing percentage figures apply to acids introduced in liquid or solid form. Where a gas is employed, as by bubbling through the oil, the quantity of reagent obviously cannot be measured in this same way, particularly since if any gas is adsorbed, the quantity may be inflnitesimal. However, in cases where the adsorbed quantity is measurable, I prefer that the per centage should not be greater than 5%.
As to the temperatures employed, they may be varied over a wide range, although the best results are obtained at temperatures considerably above room temperature but below the boiling point of the isocolloid. When using inorganic acids the temperature should be above about 200 C., and preferably from about 250 C. to 310 or 320 0.
The time of treatment may also be varied, depending upon the starting material, the treating agent and the result desired. In general, increasing the time of treatment results in more extensive modification. The treatment temperature should ordinarily be maintained for-at least thirty minutes, and preferably forseveral hours.
The heating of the oil in the presence of the polar compound or electrolyte (modifying agent) may be done in open vessels and at atmospheric pressure. However, advantageous results are obtained when the heating is carried out in closed vessels, such as kettles. autoclaves, pipe coils, etc., to secure the desired modification with the aid of the polar compound. In such cases, the heating may becarried out under reduced or increased pressure with advantage, depending upon the results desired. For instance, heating.the mixture under reduced pressure or vacuum, advantageouslv influences the modification in some circumstances. Likewise, heating under positive (superatmospheric) pressure also is advantageous (and infiuences the modification) as when volatile solvents or volatile or unstable polar compounds or both are used and the mixture heated above the normal boiling point of such materials. Heating under pressure is also advantageous with certain oils, such as tung oil and the like. For on thing, the pressure assists in preventing the coagulation or gelling of tung oil which ordinarily occurs when tung oil is heated to 26()-280 C.
SUPPLEMENTAL TREATMENT Connmons AND AGENTS the purely organic additions mentioned post or organic solvents. Again metal soaps may also be added; for instance siccatives (driers) such as the resinates and linoleates of metal compounds and metal oxides, commonly used in the varnish industry, as is mentioned in Serial No. 143,786. Further, sulphur or sulphur compounds, such as sulphur chloride, etc., may also be used in these processes and added in addition to the polar compound. The sulphur or sulphur compounds effect further modification and produce sulphurized products. The temperature usually employed for modification (above 200 C.) being substantially above normal vulcanization temperatures, the effect of this supplemental sulphur treatment is quite different from vulcanization. If desired, this sulphurization may be effected after the primary modification, as a second stage treatment.
However, I may also effect vulcanization of my modified products, so as to produce solid, coherent and elastic products, similar in general characteristics to ordinary rubber. used for this purpose and may be added as such, or in the form of a sulphur compound, such as sulphur chloride, etc. The action of the sulphur is analogous to that which takes place in the vulcanization of rubber. Thus. accelerators or activators (zinc oxide, etc.) or both, such as usually employed in the vulcanization of rubber, may be used in my processes to accelerate vulcanization when sulphur, etc., is added. The added sulphur vulcanizes or sulphurizes my modlfled products further changing their properties, Thus, I may produce rubber-like solids, as well as liquid sulphurized products.
When making solid vulcanized rubber-like products, I employ temperatures between 120' and 180' C. for vulcanization, and from to parts of sulphur to 100 parts of the isocolloid under treatment. This vulcanization may be effected before or after modification, and accelerators and antioxidants may be added to the mix in known manner.
Two step methods for making vulcanized, modified, heat-bodied fatty oil products are described and claimed in my application Serial No. 286,800 (Patent 2,234,546). As there stated, many of those roducts are useful as rubber substitutes." Others are useful for other purposes, for instance, in the manufacture of varnishes, lac- Bulphur may be 7 quers and other liquid coating compositions, as well as in plastic compositions.
As noted above, the processes may be carried out in various ways, for instance, either in open or closed vessels as desired. In the latter case, the air can be entirely or partially displaced by another gas, such as hydrogen, C02, 80:, H18. nitrogen, etc., which influence the results obtained, these gases being used in supplement to the primary modifying agent employed. Again, in both cases such gases may be passed through the material being treated. That is, the modification can be carried out during the passage of a gas. The gas pressure can be that of atmospheric. In many cases, however, a vacuum may be used with advantage. Again, even a higher pressure of several atmospheres is to be recommended in certain cases, it being sometimes advantageous.
That is, I have further found that the results of the process vary with the nature of the gas present and also with the physical condition (pressure) of this gas. Thus I have found that a certain given starting material which is initially liquid will become slightly viscous only as a result of the electrolyte treatment, if the latter is effected under atmospheric pressure (open vessel) but more viscous if the gas is rarefied by the employment of a partial vacuum. In other cases the converse applies. When plus pressure was used the results differ again. Air gives a different result from another gas or mixtures of gases such as mentioned ante. The electrolyte treatment may be carried out either in the total or partial absence of air, by replacing the same with another gas, such as those shown ante.
A pressure treatment followed by a vacuum treatment may be used, and I have found it to be advantageous to use alternately, atmospheric or plus pressure and vacuum treatment. Such alternate treatment increases the uniformity of the distribution of the electrolyte in the organic isocolloid. In my processes, the gas may be blown or passed through the liquid mass or simply passed over the surface of the same during the heating. It is advisable in some cases, both when open or closed vessels are employed, to have a constant passage of the gas, such as those given ante, during the treatment with electrolyte.
It may be stated with reference to the action of gases, that generally speaking rarefication of the gases present, by reduction of pressure in the vessel in which the treatment is given, tends to intensify the action oi the gases in my processes.
If desired, the electrolyte may be produced in situ, that is, within the organic isocolloid under treatment, by interaction within the organic isocolloid, of substances capable of reacting under the conditions of the process to produce the electrolyte. The same applies to the gas in the presence of which the organic isocolloid is to be treated and a substance or substances may be added which evolve the desired gas during the processing. It has been found in certain cases that electrolytes and gases which are produced in situ, being in the nascent state, are somewhat more active than those added in the pro-formed state.
Likewise the organioiscolloid itself may be formed in situ during the treatment. That is, if it is desired to modify an organic isocolloid which is not a naturally occurring material and which has to be produced before it can be treated, the production of such artificial or manufactured organic isocolloid may be advantageously combined with the treatment with the electrolyte. For instance, in making modified heat-bodied fatty oils, the oil may be both heat-bodied and modified in a single step by heat-bodying .the fatty oil in the presence of the electrolyte or polar compound. To do this several hours heating at polymerization temperatures is required. Many of my electrolytes are advantageous for this purpose as they accelerate the heat-bodying and polymerization of fatty oils.
In addition to the action of electrolytes and the cooperating action of gases in effecting the colloidal transformations characteristic of my invention, an additional modification of the ultimate physical properties of the treated products can be effected by the addition to the material under treatment, of purely (i. e. metal-free) organic bodies. such as phenols, naphthols, naphthalene, chloroform, acetone, alcohols and their homologues and derivatives. These additions are supplemental to the use of electrolytes. Some -f them are solvents and assist in dispersing ne electrolyte in the organic isocolloid. The use of solvents for this purpose is also shown in my Serial No. 273,159 (Patent 1,985,230) and other prior applications.
I have also found that in my processes the colloidal transformations may be promoted by the use of rays of oscillating energy, such as ultraviolet rays, infra-red rays, X-rays, etc. That is, it is advantageous to irradiate the oil or other organic isocolloid. before or during the treatment with electrolyte. Sometimes a subsequent treatment with these rays is also helpful. Further, these rays influence and intensify the action of the gases in my processes.
EXAMPLES Example 1 A concentrated dispersion of sulphuric acid in castor oil is prepared, by mixing together 10 parts by weight of concentrated sulphuric acid and 90 parts by weight of castor oil. This mix is stored cold (at room temperature) a few hours, e. g. overnight. 1000 parts by weight of castor oil are mixed with 20 parts by weight of the so prepared 10% strong dispersion of sulphuric acid in castor oil. This mixture is heated in an autoclave for one hour at a temperature of 270 C. During this heating CO: is slowly bubbled through the mixture and the pressure is maintained at about 50 mm. Hg. Then the temperature is reduced to 250 C. and the mixture maintained at that temperature for two hours. Finally the temperature is dropped to 200 C. and the mixture held at this temperature until the modification is completed.
about two hours at 200' C. being usually required.
During all of t us beatings, the introduction of the C: gas is so controlled as not to destroy the desired vacuum. After the heat treatment is finished' parts by weight of glycerine are added and the mix heated for two hours at 200 C. in an open kettle or in an autoclave at normal atmospheric pressure. A low acid number may be obtained according to this process and the resulting oil has good drying qualities. without being increased in viscosity to a great extent.
The longer storing of the concentrated dispersion of themodifyinl agent and the oil is not essential for the effectiveness of the above example.
A dissolution promoting or dispersion promoting auxiliary agent may be added. Buch agents act to improve the color of the product obtained. pical examples of the inorganic auxiliary a nts of this kind in my processes are earthy compounds, such as fuller's earth, silica gel, mica, infusoria earth, diatomaceous earth. clays, caolin and other silicates. The application of these may be illustrated in the following example:
Example 2 A concentrated sulphuric acid dispersion is prepared by mising 10 parts by weight of concentrated sulphuric acid and parts by weight of fuller's earth. 1000 parts of castor oil and 20 parts of this sulphuric acidfuller's earth mix is heated in the same manner as described in Ex ample l. The resulting product is a light colored fast drying oil, useful in the preparation of paints, varnishes, enamels, lacquers and other protective coating compositions.
Another modification of my process, to obtain light colored fatty oil products, is to use an electrical field to accelerate the action of the acidic polar compounds.
The changes brought about in the castor oil in accordance with the foregoing examples may be of a chemical or a physical nature, or both. In any event, modification may be brought about in other oils, such as linseed, soya bean, or fish oils. For instance, linseed oil may be treated with the 10% strong sulphuric acid-castor oil solution in the manner described above in Example 1. Also. in Example 2, soya bean oil may be substituted for castor oil.
Example 3 300 grams linseed oil and 15 grams of chlorsulphonic acid were heated-in a one-liter distilling flask under vacuum of 29 inches of mercury. The temperature was gradually raised to 300 C. The liquid blackens as soon as the modifying agent is mixed into the oil and at relatively low temperatures frothing occurs. However, after heating for about 15 minutes, C. was reached and the froth subsided. Upon reaching 300 C. gentle boiling sets in. The mixture was kept for about 5 hours at 300 C., and then poured out, yielding a viscous brown oily mass having a dark color.
Example 4 .Example 3 was repeated in an open glass-lined iron beaker. On addition of the reagent, dark lumps were formed and frothing occurred. The froth subsided upon reaching C. At that temperature a gentle boiling sets in. The oil was heated to 280 C. in 20 minutes and then the temperature was raised to 300' C., where the reaction mass was kept for 5 hours. Upon cooling, the reaction product obtained was a dark brown very heavy oily mass. having somewhat higher viscosity than the product of Example 8.
In the above specification the increased drying velocity of oils. e. g. if treated according to the disclosed processes with modifying agents, means alwayas comparison with an oil, treated in the absence of such polar ccmpoimds, but otherwise under similar conditions. The oils, when heated to polymerizing temperatures, change their body. viscosity and to lesser degree also their drying velocity. The action of the polar compounds may be observed if we compare the resulting product to an oil, treated under similar conditions, heated to the same temperature and for the same time, but in the absence of polar compounds. The
increased rate of drying frequently causes also an increased rate of bodying of the oils, all other conditions being equal.
During my processes complex changes usually. occur, in the presence of acidic polar compounds as a result of which new, improved modified products are obtained from fatty oils. For instance, if oils are heated to temperatures above 200 0., water and hydrogen may be given off by the starting material, accompanied by complicated changes in those starting materials, such as condensation, polymerization, shifting of double bonds, dehy droxylation, decarboxylation, amongst others. In any event, in my processes such changes as result in increasing the drying velocity and effecting other improvements in the properties of the starting materials are accelerated by the presence and action of my aforesaid polar compounds; at least beneficial and desirable results are obtained. although it is impossible to ascertain the exact mechanism by which they are obtained in. each particular commercial embodiment of my present invention.
1. In the manufacture of improved, modified products, suitable for plastic and coating compositions, from fatty oils, fatty acids, esters of fatty acids, and from materials containing the same, said modified products having increased drying velocity and other improved properties, the step which comprises heating said materials in the presence of a minor amount of an inorganic acid at a temperature of at least 200 C. and for a time sufiicient to modify the physical properties of and increase the drying velocity of said materials, said heating being continued for at least 30 minutes and the amount of inorganic acid being not more than 2. The process of claim 1, wherein said material is a fatty oil.
3. The process of claim 1, wherein said material is a non-drying oil.
4. The process of claim rial is a semi-drying oil.
5. The process of claim 1, wherein said material is a drying oil.
6. The process of claim 1, wherein said material is castor oil.
7. The process of claim 1, wherein-said material is soya bean oil.
8. The process of claim 1, wherein said material is linseed oil.
9. The process of claim 1, wherein said acid is a polybasic acid.
10. The process of claim 1, wherein said acid is a sulphur containing acid.
11. The process of claim 1, wherein said acid is sulphuric acid.
12. The process of claim 1, wherein said acid is phosphoric acid.
13. The process of claim 1, wherein the treating agent is the gaseous anhvdride of sulphurous acid.
14. The process of claim 1, wherein the treating agent is the gaseous anhydride of sulphurous 1, wherein said mateacid and wherein the heating is carried on under superatmospheric pressure.
15. The process of claim 1, wherein the treating agent is the gaseous anhydride of sulphurous acid and is bubbled through said material.
16. The process of claim 1, wherein said material is castor oil and wherein said acid is sulphuric acid.
17. The process of claim 1, wherein said material is soya bean oil and wherein said acid is sulphuric acid.
18. The process of claim 1, wherein said mate rial is linseed oil and wherein said acid is sulphuric acid.
19. The process of claim 1 wherein said material is also treated with sulphur at a temperature of at least 200' C.
20. In the manufacture of improved, modified products, suitable for plastic and coating compositions, from'fatty oils, fatty acids, esters of fatty acids, and from materials containing the same, said modified product; having increased drying velocity and other improved properties, the step which comprises heating said materials in the presence of a minor amount of an inorganic acid at a temperature of at least 200 C. and for a time sufiicient to modify the physical properties of and increase the drying velocity of said materials, said heating being continued for at least 30 minutes and the amount of inorganic acid being from .01% to 9%.
21. The process of claim 20, wherein said acid is a monobasic acid.
22. The process of claim 20, wherein said acid is hydrochloric acid.
23. The process of claim 20, wherein said acid is nitric acid.
24. The process of claim 20, wherein said acid is sulphuric acid.
25. In the manufacture of improved, modified products, suitable for plastic and coating compositions, from fatty oils, fatty acids, esters of fatty acids, and from materials containing the same, said modified products having increaseddrying velocity and other improved characteristics, the steps which comprise first preparing a strong dispersion of an inorganic acid in a batch of a fatty oil, and thereafter adding a minor amount of said strong dispersion to a batch of fatty oil to be treated, and heating the mixture at a temperature of at least .200 C. and for a time sufficient to modify the physical properties and increase the drying velocity of the fatty oil being treated.
28. The process of claim 25, wherein said inorganic acid is sulphuric acid.
27. The process of claim 25, wherein the oil used in preparing said strong dispersion is the same oil as that of the batch to which said strong dispersion is added.
28. The process of claim 25, and further including the steps of adding a minor amount of giycerine to the treated batch, and heating this mixture, to reduce the acid value of the modified oil.
nAszLo sum cen'rrncmiz 01 CORRECTION. Pate t No. 2,29 s,-916. October 13; 191 2.
It is hereby certified that error appears 1h the printed specification of the above numbered patent requiring correction as follows: Page 2, first column, line 27, for Sulphurous (H s0 SO read -Sulphurous (H 50 s0 and second column, line 11-12, for the word treatment read "treating"; 'end that the said Letters Patent should be read with this correction theregzih thab the same mey conform to the record of the case in the Patent Office Signed and sealed this 22nd day of December, A. D. 1911.2.
Henry Van Arsdale, (Seal) Acting Commissioner of Patents.
CERTIFICATE 013' CORRECTION. Patent No. 2,298,916.' v October 1 191m.
It is hereby certified that error appears 111 the printed specification of the above numbered patent requiring correction as follows: Page 2; first column, line 27, for "Sulphurous (H 's0 sO read --Su1phurous (H 30 S0 and second colu n'm, line 11-12, the word "treatment' re'ad "treating";
that the said Letters Patent should be read with this correction therethat the same may: conform to the record of'the case in the Patent Office. Signed and sealed this 22nd day of December, A. D. 1912.
fien'ry Van Arsdale, (Seal) Acting Commissioner of Patents.