US2323471A

US2323471A - Lubricating composition

Info

Publication number: US2323471A
Application number: US381133A
Authority: US
Inventors: Irvin W Humphrey
Original assignee: Hercules Powder Co
Current assignee: Hercules Powder Co
Priority date: 1941-02-28
Filing date: 1941-02-28
Publication date: 1943-07-06
Anticipated expiration: 1960-07-06

Description

Patented July 6, 1943 UNITED STATES PATENT OFFICE" LUBRICATISZiZZLIPOSITION A Q A Irvin W. Humphrey, Wilmington, Del., assignor to Hercules Powder Company, Wilmington, Del., a corporation of Delaware No Drawing. Application Februa -y 28,1941, Serial No. 381,133

16 Claims.

This invention relates to greases and high viscosity oils. More particularly, it relates to improved greases and high viscosity oils containing various metallic salts derived from rosin.

The problemof building up a grease from a lubricating oil or that of increasing the viscosity of a lubricating oil is one which has for some time past been a perplexing one. It came to be known that rosin oils of various grades when added in the form of their metallic salts would accomplish, at least in' part, the desired result. In particular, the fraction of gum rosin oil known as kidney rosin oil" produced better greases and oils than did the others. Additional materials which have been employed to accomplish the desired end include the metallic resinates of both wood and gum rosin. The use of these materials, however, has not met with great success. 1

As the need develops for lubricating greases and oils of still higher viscosity, it becomes apparent that the capacity of the rosin oil type reagents is not commensurate with that required to produce acceptable products. These reagents fail to produce the heavyviscositiesrequired; and furthermore, when incorporated in greases in large amounts, they impart a graininess or non-uniformity to the dispersion or solution as the case may be.

Particularly, with regard to the manufacture of so-called sett" greases, the prior art materials have presented difficulties. In making these products, asmall quantity of rosin oil, for example, is mixed with a lubricating oil of light viscosity. Unslaked lime is then stirred in. This is followed by the addition of water. Upon standing, the mixture sets up, forming the "sett component of the grease. A so-called prepared oil is made by dissolving rosin oil in a lubricating oil of higher viscosity than that of the oil need in the sett component. The prepared oil is then mixed with the sett and allowed to stand until the grease forms. In preparing this typ of grease using the prior art reagents, the results have been unsatisfactory inasmuch as the products do not possess the desired smoothness, nor do they have good setting-up characteristics.

It is an object of this invention to produce lubricating greases and oils having heavier viscosities or consistencies than those obtainable by prior art methods.

A further object is to produce lubricating greases and oils containing a metal resinate having a metal content higher than that of the metal resinate heretofore used.

It is also an object to produce lubricating greases and oils which are smooth .in texture and which are not characterized by graininess or non-uniformity of dispersion or solution as the case may be. I

Other objects of the invention will appear hereinafter.

These objects have been attained by employmg as the bodying agent in the ll ase or oil a metallic salt of .a rosin which has been polymerized in accordance with the various methods therefor. For example, it has been found that rosin dissolved in a suitable solvent, such as, benzene, when contacted with sulfuric acid catalyst, undergoes a metamorphosis. After the catalyst has been removed, the resulting material may be used to produce metallic salts which in turn may be incorporated in lubricating oils.

The resulting greases and high viscosity oils have much heavier consistencies than were formerly obtainable, and they are characterized by a smoothness and homogeneity which cannot be duplicated by, the products of the prior art.

The product in accordance with this invention comprises a solution or dispersion of a metallic salt of a polymerized rosin in a lubricating oil. Water may be added and emulsified therein to constitute an internal phase. The finished prodnot may also contain relatively small amounts of talc, graphite, etc. which hereinafter will be called lubrication assistants.

The metallic salts of polymerized 'rosin contemplated by this invention maybe produced from the polymerized rosin by heating the polymerized rosin to an elevated temperature, preferably within the range .of from about C. to about 315 C., accomplishing thereby the melting of the polymerized rosin. The metal is then added, in the form of its acetate, oxide, hy-

droxide, or other reactive compounds, and the heating continued until the reaction has pro-v gressed to the desired extent. While it is contemplated that any metal in the form of an apprporiate reactive compound may thus be used to produce polymerized rosin salts which may in turn be used to yield an improved oil. or grease, it has been found that metals coming within certain well-defined categories are of preferred utility. Thus, it has been I found that the alkali metals comprising sodium, potassium, etc., and the metals of group II of the periodic table comprising calcium, zinc, barium, magnesium, etc. are so preferred. Other metals, particularly de-' sirable but which fit in no well-defined group, comprise lead, aluminum, tin, and chromium. In the manufacture of the metallic salt of polymerized rosin, it is preferred to use the metal compound hereinbefore described in an amount which falls within the range between the amount necessary to produce the neutral salt of the acid constituents of the polymerized rosin and the amount which corresponds to a 100% excess. The metal compound may be used, however, in an amount which falls within the range between that necessary to produce neutralization and a 100% excess over that requiredfor complete neutralization of the acid constituents of the polymerized rosin.

The polymerized rosins contemplated to be used in accordance with this invention may be those derived from any of the various grades of wood or gum rosin. It is contemplated, too, that the various polymerized rosin acids obtainable from the aforesaid rosins be included as equivalents. These acids comprise abietic, pimaric, sapinic, sylvic, etc. acids, or mixtures thereof. Polymerization may be carried out by various methods, such as, for example, by treatment with various catalysts, as sulfuric acid, boron trifiuoride, stannic chloride, zinc chloride, aluminum chloride, hydrofluoric acid, etc., or by treatment of the rosin with a high voltage, high frequency discharge, or by treatment with an acid sludge formed by treatment of rosin with sulfuric acid. Polymerized rosins prepared by treatment of rosin with sulfuric acid or with an acid sludge formed by treatment of rosin with sulfuric acid, however, are preferred. The polymerization of rosin by any of these methods is usually carried out with the rosin dissolved'in some suitable organic solvent, such as, benzene, gasoline, etc. It is desirable in general to use a polymerized rosin which has been obtained from a rosin from which most of the color bodies have been removed by a prior treatment. Furthermore, it is contemplated that the polymerized rosin of the present invention include those that have, after polymerization, been further refined by means of selective solvents, such as, furfural, phenol, etc. or also by means of adsorbents, such as fullers earth, activated carbon, etc. This refined rosin may be then further refined by a bleach treatment, such as, subjecting the rosin to the action of zinc and sodium bisulphate, heat and carbon dioxide, etc.

These polymerized rosins are characterized by having a melting point, as determined by the Hercules drop method, above that of ordinary rosin and below about 176 C., and an acid number of from about 110 to about 165. It is preferred, however, to use a polymerized rosin having a drop melting point of from about 90 C. to about 176 C., and an acid number of from about 120 to about 165. The polymerized rosins having a drop melting point of from about 135 to about 176 C. are obtained by reduced pressure distillation of products obtained upon treatment of ordinary rosin with a catalyst, etc. In this way the unpolymerized portion of the rosin is either wholly or partially removed.

When rosin is polymerized by means of H2804, an acid sludge is often separated during the processing. By suitable treatment of the sludge, the polymerized rosin constituents in the sludge may be recovered. This recovered polymerized rosin is dark in color, has a drop melting point of from 120 to 155 C., and has an acid number of from 120 to 145. It may be used equivalently as all or part of the polymerized rosin hereinbefore mentioned.

In the general preparation of greases and high viscosity lubricating oils in accordance with this invention, several alternative processes may be employed. The metallic salts of polymerized rosin may be prepared as hereinbefore described and heated to a temperature ranging from slightly above their melting points to about 260 C. The desired quantity of lubricating oil may then be added thereto. Alternatively, the lubricating oil and polymerized rosin may be heated at a temperature of from about C. to about 140 C. until the rosin has dissolved completely in the oil, and the metal compound added thereto. The total amount of polymerized rosin present in the grease in both combined and uncombined form will be not more than 60% and preferably within the range of from about 5% to about 50% based on the weight of the total composition. An exception to this is presented where an aluminum compound is used in the process of making the grease. In that case, the total amount of polymerized rosin in the grease will be not greater than about 25%; and preferably, the total polymerized rosin present will be not greater than about 15% based on the total composition.

It will be understood that it is contemplated that the improved greases of this invention be prepared by employing precipitated" resinates obtained from polymerized rosin, although this procedure is not the preferred one. Thus, polymerized rosin may be dissolved in a suitable solvent and the desired metal compound added thereto. The resulting precipitated resinates may, after separation from the solvent, be incorporated in lubricating oil to produce the desired grease.

The lubricating greases or oils prepared in accordance with this invention may contain water emulsified therein to the extent of from about 1% to about 10% based on the total composition. Lubricating assistants such as graphite, powdered mica, etc. may be added to the extent of from about 0.5% to about 25%. Both the water and the lubrication assistant may be added during the processes hereinbefore described or thereafter. a

In the particular instance where a sett oil is prepared in accordance with this invention, polymerized rosin is dissolved in'a quantity of lubricating oil by any suitable means. Desirably, this may be accomplished by heating the mixture at a temperature of from about C. to about C. After solution has taken place, a suitable metal compound, as hereinbefore described, is added and the whole agitated. This constitutes the sett. A "prepared oil is made by dissolving polymerized rosin in another quantity of lubricating oil. This prepared oil is then admixed with the sett. time the mixture sets up forming a grease.

It will be understood that any lubricating oil may be used in producing the improved products of this invention. Although oils having particular viscosities are used in the specific examples,

it is intended that the broad concept herein disclosed be in no way limited thereby. Actually, the particular oil chosen in any case will depend upon the final disposition of the grease or oil produced.

The following specific examples are given as illustrative of particular embodiments of the invention. The polymerized rosin employed in the Upon standing for a first four examples was produced from rosin by treatment with sulfuric acid catalyst and had a melting point by the Hercules drop method of 100 C. It was thereafter refined by subjection to heat treatment in presence of carbon dioxide. All parts and percentages throughoutthe specification and claims attached are by weight unless otherwise stated.

The lubricating oil (A), having a viscosity at 100 F. of 100 seconds in a Universal Saybolt viscosimeter, and the 25-part portion of polymerized rosin were heated and agitated at 93 C. until solution was efiected, after which the lime was slowly stirred in. A light brown "sett resulted. Then, the lubricating oil. (B), having a viscosity at 212 F. of 235 seconds in a Universal Saybolt visc-osimeter, and the 200-part portion of polymerized rosin were heated at 93 C. with agitation I until solution was efiected. This constituted the oil. Holding the temperature of this prepared" oil at between 53 C. and 65 C., it was stirred into the sett." A standard sett grease was prepared using equivalent quantities of unpo-lymerized rosin. Upon comparison, the grease containing polymerized rosin was much smoother and had a decidedly heavier consistency.

"prepared EXAMPLE 2.

. Parts Polymerized rosin 39.45 Zinc oxide .55, Lubricating oil 60.00

The polymerized rosin was melted and the temperature run to a maximum of 232 C. At this maximum temperature the zinc oxide was slowly added. After the zinc oxide had completely reacted, the temperature was allowed to fall to 215 C., at which point the lubricating oil was added. This particular oil had a viscosity at 100 F. of 100 seconds in a Universal Saybolt viscosimeter. A smooth viscous grease resulted. A standard made by the same process with the exception that WG wood rosin was substituted for the polymerized rosin was grainy, less viscous and of definitely darker color.

ExAMPLn 3 Parts Polymerized rosin 39.15 Litharge 0.85 Lubricating oil 60.00

The polymerized rosin was melted and the temperature increased to 232 C. At this temperature the litharge was added and the temperature slowly raised to 274 C. After complete reaction had taken place with the litharge, the temperature was allowed to fall to 260 C. At this temperature the oil, having the same characteristics as that used in Example 2, was slowly stirred in. A smooth, more viscous grease than that produced in a similar manner with the use of unpolymerized rosin resulted.

i EXAMPLE 4 l Parts Polymerized rosin ....L-.'. 10

Aluminum propoxide (employed in the form of a 37% solution in propyl alcohol) 2.07 Lubricating oil The lubricating oil, havingthe same characteristics as that of Example 2, and polymerized rosin were heated with agitation at 93 C. until solution was eifected. The temperature was then allowedto rise above 107 C. After complete solution had been eifected, the temperature was allowed to fall to 82 C., at which temperature the aluminum propoxide solutionwas stirred in. Upon standing, a grease having better color and definitely improved viscosity characteristics, when compared with a standard made using un- ,polymerized rosin, resulted.

EXAMPLE 5 Sett 1 Parts Polymerized rosin 10 Lubricating oil (A) 30 Calcium oxide u 3.5 Water -1 15 Prepared oil Parts Polymerized rosin 30 Lubricating 011' (B) 50 The polymerized rosin .used in this example was one obtained from anacid sludge which.

resulted from the treatment ofv unploymerized rosin with sulfuric acid. The lubricating -oil (A), having a viscosity at F. of 100s'econds in a Universal Saybolt viscosimeter, and

the 10-part portion of polymerized rosin were heated with agitation to C. When the polymerized rosin had completely dissolved, the solution was cooled to 90 C. and the calcium oxide was stirred in. The water was then added accompanied by vigorous agitation. "The resulting material constituted the sett." "The'lubrieating oil (B), having a viscosity at 100 F.'of 500 seconds in a Universal Saybolt viscosimeter, and the 30-part portion of polymerized rosin were heated at C. and held there until solution was effected. This solution constituted the prepared oil. Holding the temperature of this prepared oil at between 53 C. and 65 C., it was stirred into the sett. A grease having a very smooth texture and heavy body set upon standing.

By the use of the metal salts of polymerized rosin in accordance with the instant invention, it is possible to produce lubricating greases and high viscosity lubricating oils in which there is no graininess or non-unformity of solution or dispersion. In addition, these improved greases have better color than those of the prior art. Another advantage observed is the production of lubricating greases and oils which have much higher viscosities than those previously obtainable by prior art methods. A'still further advantage offered by the use of metal salts oi polymerized rosin in the production of greases and high viscosity oils is found in their yielding compositions containing greater quantities of metal in the form of the resinate than have heretofore beenpossible using identical proportions of rosin. Increased viscosities and better setting-up properties result therefrom.

It will be understood that the details and examples hereinbefore set forth are illustrative only and that the invention as broadly described and claimed is in no way limited thereby.

What I claim and desire to protect by Letters Patent is:

- 1. A lubricant, comprising a lubricating oil and a metal salt of polymerized rosin in sui'iicient quantity to substantially thicken the oil.

2. A lubricant comprising a lubricating oil and a metal salt of polymerized rosin wherein the metal is selected from group 2 of the periodic table, said salt of polymerized rosin being present in suflicient quantity the oil.

3. A lubricant comprising a lubricating oil and an alkaline earth metal salt of polymerized rosin in sumcient quantity to substantially thicken the oil.

4. A lubricant comprising a lubricating oil and a calcium salt or polymerized rosin in sumcient quantity to substantially thicken the oil.

5. A lubricant comprising a lubricating oil and an alkali metal salt of polymerized rosin in sufflcient quantity to substantially thicken the oil.

6. A lubricant comprising a lubricating oil and a sodium salt of polymerized rosin in suflicient quantity to substantially thicken the oil.

7. A lubricant comprising a lubricating oil and a lead salt of polymerized rosin in suflicient quantity to substantially thicken the oil.

8. A lubricant comprising a lubricating oil, a metal salt of polymerized rosin, and containing water emulsified therein, said salt of polymerized rosin being present in sufilcient quantity to substantially thicken the oil.

9. A lubricant comprising a lubricating oil, a metal salt of polymerized rosin, a lubrication assistant, and containing water emulsified therein, said salt of polymerized rosin being present in suflicient quantity to substantially thicken the oil. I

10. Alubricant comprising a lubricating oil, a metal salt of polymerized rosin, powdered graphite, and containing water emulsified therein, said salt of polymerized rosin being present to substantially thicken in sumcient the oil.

v 11. A lubricant comprising a lubricating oil and a calcium salt 01' polymerized rosin, the total polymerized rosin present in both the combined and uncombined i'orms being not greater than about 60% by weight based on the finished product and said salt or polymerized rosin being present in sufllcient quantity to substantially thicken the oil.

12. A lubricant comprising a lubricating oil and a sodium salt of polymerized rosin, the total polymerized rosin present both in the combined and uncombined forms being not greater than about 60% by weight based on the finished product and said salt of polymerized rosin being present in sufilcient quantity to substantially thicken the oil.

13. A lubricant comprising a lubricating oil and a lead salt of polymerized rosin, the total polymerized rosin present in both the combined and uncombined forms being not greater than about 60% by weight based on the finished product and said salt of polymerized rosin being present in suflicient quantity to substantially thicken the oil.

14. A lubricant comprising a lubricating oil and a calcium salt of polymerized rosin, the total polymerized rosinjpresent in both the combined and uncombined forms being within the range of from about 5% to about 50% by weight based on the finished product.

15. A lubricant comprising a lubricating oil and a sodium salt of polymerized rosin, the total polymerized rosin present both in the combined and uncombined forms being within the range of from about 5% to about 50% by weight based on the finished product.

16. A lubricant comprising a lubricating oil and a lead salt of polymerized rosin, the total polymerized rosin present both in the combined and uncombined forms being 'within the range of from about 5% to about 50% by weight based on the finished product.

IRVIN W. HUMPHREY.

quantity to substantially thicken