CA1041473A

CA1041473A - Rust inhibited lubricant composition

Info

Publication number: CA1041473A
Application number: CA200,185A
Authority: CA
Inventors: Haakon Haugen; David G. Weetman
Original assignee: Texaco Development Corp
Current assignee: Texaco Development Corp
Priority date: 1973-05-21
Filing date: 1974-05-17
Publication date: 1978-10-31
Also published as: BE815144A; FR2230715A1; SE403299B; NL7406719A; GB1455476A; JPS5041905A; IT1012697B

Abstract

RUST INHIBITED LUBRICANT COMPOSITION
(D#72,955-Cl-F) ABSTRACT OF THE DISCLOSURE
Rust inhibited lubricating oil composition comprising a major portion of a mineral lubricating oil, an overbased alkaline earth metal compounds and a minor amount of a trialkanolamine represented by the formula:

in which R is a hydrocarbyl radical having from 1 to 24 carbon atoms.

I

Description

9 (J~ 73 .:
This invention pr_rtain~ to a lot~-ash mineral lubricatin~ oil composition which has been Inodi~iec1 to enhance its rust inllibitincJ properties by the a~dition thereto of a hy~rocarbyl ~u~stituted trial~nolamine com-pound~ The lubricating composition is particularly efficacious for a~elioratinq rustinq in intorllal com-bustion enqines that is especially prevalent durin~ cold 10~ engine operation observed in short trip service.
- - .
.' ' ~ .
- ', ' U.S~ 1,888,023 discloses a color-stabilized lubxicating oil composition containing a primar~, second-ary or tertiary allphatic ~minc or hydroxyaLkyl~mine.
i U.S. 2,353,83~ dl~iclose.s a lubr1cant ~or~an a'r pump co..'a~ g tri-ethanolamin~ stearate and co~ris-ing ~ 0 percent of water. -~ ' ~
U.S. 3,458,~44 discloses a rust inhiblted ~ mineral lubricating oil composition containing the reaction ,~ 20 ~ product of an alkenylsuccinic acid or anhydride and an N-hydrocarbyl diethanolamine.

.

This invention pcrtains to ~ rust inhibited lubricatiny oil~composition comprisiny a mineral oil base, ~ -. an overbased alkaline earth m~tal compound and a minorrust inhibiting amount of a subst~ituted trialkanolamine represented by ~t~he formula~

~ ~ . . , , , - ,... . . : . .

~ ~L()4~73 ::
H H
. . . . .
R - C - C - N - (CH2 - CH2 -OH)2 OH H
in which R is a hydrocarbyl radical having from 1 to 24 carbon atoms.
A preferred aspect of the invention is a lubricant comprising a major portion of a mineral lubricating oil having an SUS viscosity at 100F. in the range of 50 to 300 containing said overbased alkaline ; 10 earth metal compouna and from about 0.01 to about 1.5 weight percent of the prescribed substituted trialkanol-amine.
The lubricant of this invention will commonly be employed in the form of a fully formulated lubricating : .
oil composition containing a variety oE conventional i lubricating oil additives designed to impart improved ! ~ viscosity index, oxidation resistance, load carrying ;~
j~ properties, etc. The lubrlcant of the invention is particularly effective in the formulation of a relatively `
low ash, crankcase motor oil composition.

1 ~
I DETAILED DESCRIPTION OF THE INVENTION

~:;
The substituted trialkanolamine employed in lubricant of this invention is represented by the general ormula:
H H .
; R - ~ C - C - N ~ (CH -~CH -OH)2 OH H

3;0 D: ~ ~

: A preferred class of substituted trialkanol-amines are those represented by the formula:
H H
. R - C - C - N = (CH2 - CH2 - OH)2 OH H
in which R has the value noted above. A more preferred :
substituted trialkanolamine is one in which R has from 3 to 16 carbon atoms and a still more preferred trialkanol-amine is one in which R has from 8 to 14 carbon atoms.
: 10 In another feature of the preferred compunds, R is a ~;: ;.
straight chain saturated aliphatic hydrocarbon radical. . .
The substituted trialkanolamine employed .~ .
'. herein is most conveniently obtained by reacting an ~:
.,.
I alpha olefin epoxide compound with a dialkanolamine. .~ .
! This reaction is conducted by reacting approximately ~! one mole of the alpha olefin epoxide with a mole of .
dialkanolamine. This invention contemplates the use of ;~
higher or lower mole ratio of the dialkanolamine in .
.3~ this reaction with the resultant reaction product . ~ ~

2 ::
~ 20 ~ comprising a mixture containing in addition to the `~
j~ prin~ipal product some other closely related products, ¦ : such as products derived from the reaction of an epoxide .
with greater than one mole o~ diethanolamine. It is :.
contemplated that such mixtures can be beneficially ~ :,:- :

3 ~ employed in the lubricant o~ the inven~ion.

1~ : .::

:

~ /

~ . .. : .

- In ~en~ral, the reac-tion pl-oce~cls in clccordance with the ~c~llowin~ formula ~herein the symbols have the values noted herein above.

Z
R-CII-~EI-R' ~ HN=(c~l-[cH2]x - C~IOEI)2 -H R' z y R-C-C-N = (CH-ECH2]X - C~lH)2 10 _ . OH H
Tlle olefin epoxide reactant which can be employed is a straight chain aliphatic hydrocarbon having from 1 to ~. :
about 24 carbon atoms. These compounds are generally characterized by having an olefin oxide functional group at one end of the chain. The compounds are typically . .
obtained in commerce as mixtures of alpha olefin epoxides.

The mixture of Cll to C~4 alpha olefin epoxides and a . mixture of C15 to C18 alpha olefin epoxides are typical of the xeac~ants employed for preparing the additive and . . .
2Q lubricant of the invention and to produce the products that are'preIerre~ species of th i~t~ntion.
Examples of suitable olefin epoxlde reactants~
are liste~ in Table I below:

.. . . . .
TAB~E I

1,2-epoxyoctane 1,2-epoxybutane 2,3-epoxyoctane 1,2-epoxypropane

4,5-epoxyoctane 1,2-epoxyhexane 1,2-epoxydo{lecane 2,3-e~oxypentane 1,2~epox~hexadecane 2,3-epoxybutane 30 ~- 1,2-epoxyoctadecane 3,4-epoxydecane 2,3-epoxydecane 1,2-epo~ytetradecane 1 The~dialkanolamine reactant can-be~a sin~le com-~ , pound or a~mixture of compounds within the prescribed formula~inoluding those illustrated below.

~, . .
;~ . . . . . . .

~L~41473 T~}31E II
____ _ diethanol~mine , . . diljropanolamine diisopropanolamine dibutarlola~ine ; diisobutanolamine dipentanolamine aiisopentanolamine The reactants.are brought toqether in a reaction 10~ v~ssel and ~radually heated until the reaction commences which will generally be in the range of 80 to 120C.
Since the reaction is exothermic in nature, heatinq is j discontinued when the exotherm begins. The reaction ;i temperature increases autogenously to a ran~e of 170-190C.
The reaction mixture is maintained in this temperature range for about 5 to 30 minutes after which the reaction j~
product is allowed to cool. Any compounds of the types '~ illustrated in Table I can be reacted with those illustrated ~ in Table II to produce the pxescribed substitutecl trial-s 20 kanolamineO
! ~ The following examples illustrate the prepar-:. - . : ..
i~ ation of spècific ashless substituted trialkanolamine additives employed in the present invention. ~ i s: , , : : . .
EXAMPLE I
484 grams ~2.0 mole) of C15-C18 straight-chain alpha olefin epoxide mixture and 210 grams (2.0 mole) of 'l' . ' .' diethanolamine were charyed to a reaction vessel. The stirred mix~ure was gradually heated to 100-12QC. at which~point an exothermic reaction occurred. External heatlng~was di~scontinued~ whi1e the heat of reaction carried the~temperature of the mixture to 170-190C. The reaction mix~ure~was kept within this temperature ranye or about 0,25-0.50 hours. The mixture was then cooled to room tem~erature and~685 grams of product were recovered.

i, / ~....................... , . :

~ 1473 X~ML'IE II
827 grams (~.25 ~ole) of Cll-C14 strai~ht-chain alpha olefin epoxidP mixture and 445 grams (4.25 ' moles) of di~thanolamine were char~ed to a xeaction vessel ', and reacted and recovered as in Example I above. 1204 grams of product were realized.
EX~MPLE III ,~

Reaction of 1,2-epoxyoctane ' ' and diethanolamine (R-C ) 390 grams (1.0 moles) of 1,2-,epoxyoctane and 315 grams of diethanolamine t3.0 moles) were charge~ to a reaction vessel and reacted as described in Example I
above. 705 grams of product were realized.

EXAMPLE IV
' i Reaction of 1,2 Epoxybutane and diethanolamine (R=C2) ._, .
1' 144 grams (2.0 moles) of 1,2 epoxybutane and '~' ' l~ 210 grams of diethanolamine;(2.0 moles) were charqed ,to a '¦` , ' reaction vessel and reacted a's described in ExampIe I of 20 above. 354 grams of product were realizea.

The~base oil for the lubricant of the invention~
.
an be predominantly paraffinic or naphthenic or it can be a mixture of both types o mineral oils.~ In general, the;
base oil wlll be a relatively highly reined mineral oil of predominantly paraffinic nature and will have a viscosity ~ ,, in the range of`about~50 to about 500 Saybolt Universal Seoonds at 2~10F.
' The substituted trlalkanolamine additive of the~invention is particularly uaeful for preparing a , relativ~ly low ash rust-inhibited lubricating oil composit=~
ion~. ~ This invention contemplates the use of the sub~
stituted trialkanolamine compound in conjunction with an' -~l~141~3 overbased alkaline earth metal compound rust-inhibitor to product a relatively low ash rust-inhibited lubricating oil composition. . ... -, The overbased alkaline earth metal rust inhibitors are old and well known and are generally suitable in the lubricating oil .~: .
composition of the invention. There is no criticality in the `. p~.
particular choice of the overbased alkaline earth metal rust ~:
inhibitor. The preferred rust inhibitors are the overbased calcium . ~ ~
~ sulfonates and car.boxylates in which the sulfonate or carboxylate ..

i portion has a molecular weight from about 300 to 600 and in :
1 10 which the compound has a metal ratio greater than 1 up to about . ;. :.

i 5. The basicity of the overbased alkaline earth metal compound can also be expressed as a total base number (TBN). ..
Only a minor amount of the overbased alkaline earth . .:
metal compound is necessary to provide the improvement of this invention. The broad concentration range for this component is , from about 0.01 to 0.5 weight percent. Outstanding results are, ~ .
however, reali~.ed when from 0.01 to 0.15 weight percent of the overbased alkaline earth metal compound is employed. A particular- :: ;;.' ly effective lubricant is a balanced composition comprising the ^ .
prescribed substituted trialkanolamine additive in conjuction ~ -. .~ :
with a basic alkaline earth metal salt of sulfonic acid or a carboxylic acid.
It is understood that a concentrate of hydrocarbyl- .
I substituted trialkanolamine and of the overbased alkaline earth !
metal compound can be prepared in a suitable : .

.`:'; "'`:-~ G
.. ~ .....

. i .. , .. . .. . .. .. . . ... .. , , . . . . .. ... ., . .. , . ~ . ... ~ . .. . . .

~ 1)4~473vehi.~ hicll C.lll b~ enlploye~ fro~l ~reparin~ the lu~ricating oi]. conlpositit~n of th~ invention.
A wide range of conventional mineral oil .addit.ives can b~ employe~ in the formulation of a fully balanc~d lubxicating composition ~mployinq the improve-' 'ment of this invention. ~ffective conventional anti-oxidants include the diphenylamines, such as diphenylamine anfl the Cl to C12 alkylated di~henylamines, the phenyl naphthylamines and the methacryiate copolymers to i~prove the viscosity index of the oil.
The rust.inhibiting properties of the novel lubricant of the invent.ion was determined in the General Motors Sequence ITC Test. This Test is designed to . evaluate crankcase oils with respect to low temperature , rusting. .
.. . . .
This Tesk is run on a 1967 Oldsmobile equipped with a 425 CID V-8 engine with a 1~.25 compression ratio l using 1970 cyclinder heads equipped with a 2-Barrel carburet-.', or. The car is run on a dynamometer test stand with the necessary equipment for control of the test procedure.
. The engine is operated continuously for 28 hours .... . . .
under conditions of moderate engine speed, partially warmed-up jacket coolant temperature and rich air-fuel ratio. ;~
An additional two hours of operation at a slightly elevated acket coolant temperature and a inal two hours under higher speed ho~ conditions.~ Modera~e enqine s~eed is ~ ~
1500 + 2~0 rpm~with a load of 25 + 2~horsepower Hiqh speed ~ -operation for~ two hours~is run at 3606 to 20 rpm and a load ~; -of 100 ~ 2~brake horsepower.~
~ On completion of the test the en~ine is disassem-bled an~visually~inspected for lifter, push rod, an~ oil pump; reloase va1ve rust. ; The avcra~e~engine rust is caLcul~
ated~f~rom~the fore~oing values accordin~ to a prescr.ibed procedure.~

1. . .. ~ , , . . . :

, ~ !
The b~se oil em~loyed for preparin~ the lu1ricant of this invention was an ess~ntially paraffi~lic base oil having an SUS viscosiky at 210F. of about 40.
Lubric~tin~ oil blends were preparefl and tested for their anti-rust effect;veness in the M~-IIC Test re-- ferred to above. The compositions of the lubricants are set forth in the Table below r in each blend the balance of the composition being the p~raffinic base oil ~escribed above. The rust values for the various engine parts in ` 10 spected are indicated as well as the average enaine rust. ;
The average engine rus~ must be 8.4 or above to pass this test.
. .

, :' ' ` , ' ' ,' ` ''',:'.',"

. , , ., , ::
., ' , '`

473 : ~ ~
,t W ~ t tl t~ ~ ~ O O t'- tt X ~ ~ o (D U~ D o ~3 ~ ~ æ ~ ~ ~ ~ o lo . ~ O ~ 5 P~ t' t~ g r~ rt- ~;
c U ~;, p , (D p ,~ 1- ~1 ,'I t- tJ- r~
o - ~ ~ i~
c~ .
'~ ` o~ ~ . i~ . .
`~~ ut u~ p~ ~-t -`(D ID 5 (D ~ ~n ~ W ~Jl ~ o .P o C~ !Oz . .
tt ~ Ul W ~ . IUl Ut Ul ~ ~ 7 ~: p n t~
t Co ~ t o~ _~t O ~ O O O trt n o ~ ~ ~t o ~-- t--; tI,t tt~
rt t~ t d t~
t~ 00 o ~ t iu ~n ~ ~ Is~ tl t ~; ~J ~ æ ~
~ ~ ~ ID ~ oD DD oD ~ O ~ O t ~, ¦ c ~ 0 ~o co ~D OD I ~ O O ~ O O o . t X a~ t O ~ î 'On ~ Ul Ul ~ ~ t.~ n ~ .
rQ
)' 00 ~t co 03 oO O O ~ O o O ~ ~ '" ..
~ ~ ~ t,~ n u' ùl Ul o n ~0~ 473 In the fore~oillg Table III, lubricatin~ oil Compos-itions ~, B, ana C al-e ~ompari~son oils col~tainin~ increas-in~ amount~ of basic calcium sulfonate. None of these oil composil:ions meet the m~nimum requirement of 8.4 to pass th~ MS-IIC Tcst. Further increases in the a~ount of basic calciùm sulfonate would only serve to a~gravate the ash content lcvel of the blended oil.
Lubricating Oil Compositions D, E, F and G are representative of the present invention. Without any increase in the ash level of the blended lubricants, these oils substantially exceeded the anti-rust standards of the MS-IIC Test to provide an outstanding, relatively low ash, anti-rust crankcase lubricating oil for severe low temper-ature engine service.
Addition'al tests of the lubricants of this invention were made in the Bench IIC Rust Test. This Test .
was developed to predict the performance of a lubr1cant in the SE required MS-IIC Rust Test.
; Accordins to the Bench IIC P~ust Tcs~ a gaseous ,;~ 20 mixture of nitrogen oxides (NOx), water vapor and air is ~- simultaneously passed through a~cell containin~ a test oil ~ ;
and a cell containing a standard lubricant formulation under specified conditions of temperature an~ for a specific ' length of time. The standard formulation can be any lubricant system for which the rustin~q characteristics or average rusk rating have been established;in the MS-IIC
ngine Rust~Test; an average rust rating, obtained by visually rating the degree of rustinq on a variety of engine parts includin~pushrods, is given for each MS-IIC En~ine ~ ; 30 Rust~Test. ~ The rusting characteristics of an oil in the J
~ Bench IIC Rust~Test lS determined~by visually ratinq a 3~ section of an~engine poshrod placed in the test oll and ~ standard oil~during-th~ test. The relative deqree ~of ~ ;

10~473 ~- rusting o~ th~ pusllrocl scction surr~u1l~led by the test oil can be detcrmincd alld comparecl to that occurin~J in the standard oil. Having established the rusting character-is-tics of the standard oil in the MS-IIC En~ine Test, a prediction of the rust protecting ability o~ the test oil : under ~n~ine Test conditions can then be made. In practice,the standard lubricant employed in the E~ench IIC Rust Test is one which gives a failing rust ratiny in the En~ine Test of 6.1.; a minimum averaae rust rating of 8.4 is reguired to satisfy SF, qualification. It has been determined that an experimental formulation achievins a rust rating of 7.5 or greater in the Bench Test can be expected to achieve a passing or near passing result in the engine test.
: Lubricating oil compositions of this invention I employing the hydrocarbyl-suhstituted trialkanolamines o ! ' Examples III and IV above have been found to be superior 3 lubrical1~s ir. ~he Bench IIC ~ust Teat. Th~^ test d~ta indicates that these lubricants will substantially exceed ., the p~rformance standards of the MS-IIC Enaine Rust Test.
1 : .
. . , '' .':: ' ~ .

.; ' ' . , , ' ' ' ' , ' ",, ' '" ~ ' ~ ~ , .'"
' :. ' , . .

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A low-ash lubricating oil composition comprising a major portion of a mineral lubricating oil, 0.01 to 0.5 weight percent of an overbased alkaline earth metal compound and 0.01 to about 1.5 weight percent of a trialkanolamine represented by the formula:

in which R is a hydrocarbyl radical having from 1 to 24 carbon atoms.

2. A lubricating oil composition according to Claim 1 in which R represents a saturated aliphatic hydro-carbon radical having from 3 to about 16 carbon atoms.

3. A lubricating oil composition according to Claim 1 in which R is a saturated aliphatic hydrocarbon radical having from about 8 to 14 carbon atoms.

4. A lubricating oil composition according to Claim 1 in which R is a straight chain hydrocarbyl radical having from 13 to 16 carbon atoms.

5. A lubricating oil composition according to Claim 1 in which R is a straight chain hydrocarbyl radical having from 9 to 12 carbon atoms.

6. A lubricating oil composition according to Claim 1 in which R is a straight chain hydrocarbyl radical having 4 carbon atoms.

7. A lubricating oil composition according to Claim 1 in which said overbased alkaline earth metal compound has a metal ratio greater than 1 up to about 5.

8. A lubricating oil composition according to Claim 1 containing from 0.01 to 0.15 weight percent of said overbased alkaline earth metal compound.

9. A lubricating oil composition according to Claim 1 in which said overbased alkaline earth metal compound is an overbased alkaline earth metal hydrocarbon sulfonate.

10. A lubricating oil composition according to Claim 1 in which said overbased alkaline earth metal hydro-carbon sulfonate is basic calcium sulfonate.

11. A lubricating oil composition according to Claim 1 containing from about 0.075 to 0.35 percent of said trialkanolamine.

12. A lubricating oil composition according to Claim 1 containing from about 0.10 to 0.25 percent of said trialkanolamine.