CA1331662C - Specified c -carboxylate/vinyl ester polymer-containing compositions for lubricating oil flow improvement - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Compositions are disclosed for improving at least the low temperature flow properties of lubricating oils. The compositions are dual additives including a first component which is a polymer or interpolymer of a C14 carboxylate, such as a C14-dialkyl fumarate/vinyl acetate interpolymer, and a second component which is a lubricating oil flow improver comprising a non-ethylene containing polymer or interpolymer such as dialkyl fumarate/vinyl acetate interpolymer, esterified styrene/maleic anhydride interpolymer, or esterified olefin/maleic anhydride interpolymer.

Description

133~2 ~

F~EI~OF THE INVENTION
The pres-nt invention relatQs to additive~ for lmproving the ~low prop-rties of certain oleaginous compositions More particularly, the present invention relates to additives for improving at least the low temperature flow properties oS lubricating oil compositions, and more particularly the lubricating oil compositions which inc}ude lubricating oil flow . , improvers Still more particularly, the present invention relates to improved lubricating ~ oil composit1ons including such additives ~or improving the ~low properties thereoS More particularly, the present invention relates to mQthods for improving the flow properties oS oleaginous composit$ons, particularly engine crankcase lubricant compositions ~-BACKGROUND OF THE INVENTION : :~ ~-A wide varieey of compounds for use as lubricating oil or~ruel oil additives~ are known in this art~ Thes-~ incLude compound- variously referred to as pour~point d-prèssant-, viscosity index improving compositions, wax crystal modifiers, and the like In particu~ar~,~Cas~man e~ aI, U S Patent No 2,825,717, di-clo-e-~ the ~preparat-on~o~ certain lubricaeing oil -addieives by~th- copolym-rization of polycarboxylic acid est-r-~ with ~oeh-r~ polymeriz-ble monomeric materials, including vinyl compounds such as vinyl acetate The preferred unsaturated polycarboxylic acid esters therein ., .

- -2- 1331~
are fumaric acid esters produced from Cl through C18 aliphatic alcohols.
Bartlett, U.S. Patent No. 2,618,602, discloses pour point depressing and/or viscosity index improving materials obtained by polymerizing certain specified alkyl fumarate esters. In particular this patentee discloses the use of polymerized fumarate esters of C12 to C14 alcohols for such purposes. This patent specifically discloses that the C12 alcohol was more effective than the C14 alcohol, although both polymerized esters exhibited pour point depressing properties .
Rossi et al, U.S. Patent No. 4,088,589, discloses the use of specified mixtures of lubricating oil pour point depressants which include polyesters consisting of a polymeric ester of acrylic acid or methacrylic acid and a monohydric alcohol containing from 10 to 18 carbon atoms, and/or interpolymers of a vinyl alcoho} ester of a C2 to C18 alkanoic acid (e.g., vinyl .. . .
acetate) and a di(C6-C18alkyl) fumarate as one of the components thereof for improving the viscosity index of high wax content lubricating oils which also include viscosity index improving ethylene copolymers. Also, Wyman, U.S. Patent No. 3,250,715, discloses terpolymers of dialkyl fumarates, vinyl esters, and alkyl vinyl ethers for improving the pour point of lubricating oils, ~ .
and most particularly in which the dialkyl fumarates are prepared from various C10 through C18 alcohols including tetradecyl alcohol alone as well as alcohol mixtures averaging from I2 to 14 carbon atoms.

~ 1331~2 There has also been disclosed in U.S.
Patents 4,713,0~8 and 4,863,486, the use in various middle distillate fuel compositions for lowering the pour point and controll$ng the size o~ wax crystals in these product~ which specifically include polymers and copolymers of specific dialkyl fumarate vinyl acetate co-polymers. Most specifically, these patent applications disclose the use of such compounds in which the average number of carbon atoms in the alkyl groups in the poly-mer or copolymer must be from 12 to 14. In addition these additives are also disclosed as being useful in -~
combination with the polyoxylakylene esters, ethers, esters/ethers and mixtures therof, as well as with various other additives. Furthermore, British Patent No.

2,023,645 discloses, for use in treating distillate fuel oils, various three-component systems which include as a first component flow improvers having an ethylene backbone, such as various ethylene polymers including ethylene polymerized wieh various mono- or diesters (e.g., vinyI acetate; and C13 umarates), as a second component a lube oil pour depressant such as various oil .
- soluble esters and/or higher olefin polymers (e.g., ; dia}kyl fumarate,' vinyi acetate copolymers), and as a third component various polar oil-soluble compounds te.g., phenates, sulfonates, phosphates, and carboxylates).
It is also disclosed in Lewtas' U.S. Patent ; Nos. 4,661,121 and 4,661,122 that the size of wax y , ~ ~ , .
' ' ` . - .
.
i' ' ~4~ 1331~
cryst.als forming in fuel~ boiling in the range o~ 120-C
to SOO C can be controlled by an additive which includes . .
the polymers and copolymers of mono- and di-n-alkyl esters of mono-ethyleniCally unsaturated C4 to C8 mono-or dicarboxylic acids, in which the averaqe number of carbon atoms in the n-alkyl groups is ~rom 14 to 18.
These patents show a preference for copo}ymers of di-n-alkyl fumarates and vinyl acetate, and specifically state that the fumarates can be made from single alcohols or mixSures of alcohols, and when mixtures are used they are mixed prior to esterification. Furthermore, these patents disclose the use of various ethylene unsaturated ester copolymer flow improvers as co-additives therewith, but do not specify that these additives are produced from alcohol mixtures. Finally, in U.S. Patent 4,956,492, which is a Divisional of U.S. Patent 4,670,130 there i~
disolosed as a dewaxing aid a copolymer of dialkyl fumarate and vinyl acetate in whlch-~a large proportion of the alkyl groups ar- C20 to C24 alkyl groups.
While these various . types of additive compositions have met with. various degrees of success in the particular environm-nts in which they are employed, it has been observed that various lubricating oil compositions, such as thosel containing certain viscosity improving addit~ives, such as copolymers of ethylene and propylene, as ~w-ll as those lubricting oil compositions containing lubricating oil flow improvers, nevertheless ~ .

. ~

~ 3 ~ 2 experience difficulty in passing recently adopted, more stringent, low temperature, slow cool performance tests designed to measure the low temperature pumpability of crankcase lubricating oils. It is therefore an object of the present invention to provide additives which enhance the low tempeature pumpability of lubricating oil compositions.
SUM~AR~_QF THE INV~TION
In accordance with the present invention, these and other objectives have now been realized by a dual component additive composition which significantly improves at least the low temperature flow properties of lubricating oils and which comprises, as a first component, low molecular weight (Mn) polymers a~d interpolymers (e.g., copolymers) of unsaturated mono- or dicarboxy esters having the formula:

. ~ O -H~ C - OR
(I) \ /
. / C - C \
R' H
in which R' is either hydrogen or a COOR radical, and in which R is a cl4 alkyl group, in admixture with at least one second component of a low molecular weight (Mn) lubricating oill, flow ~impiover (LOFI) comprising !non-ethylene containing polymers which are soluble or dispersible in these lubricating oils. Indeed, it has - ---been discovered~that this specific combination provides a synergistic improvement in at least the low temperature viscosity performance of these lubricating oil .:; . ~
~'," :
~: ' ~ 6- 1 3 ~ 2 .
compositions in that the results demonstrated are superior to the additive effect obtained by using either of these components alone in such lubricating oil compositions. These highly unexpected re5ults have now permitted the formulation of lubricating oil compositions, particularly those which contain olefinic copolymer viscosîty modifying additives which exhibit enhanced slow cool, low temperature viscosity performance.
In a preferred embodiment of the dual additive compositions of the present invention, the first component thereof comprises a low molecular weight (Mn) interpolymer of at least one of the carboxy ester monomers of formu}a (I) above with a polymerizable vinyl ester monomeric compound having the formula:

: / H
(II) CH2 = C
.... O - C - R~ -~ .~ ., :. -.~;; in which Rl is an alkyl group containing from about 1 to ~ :

~ 18 carbon atoms, preferably from about l to 6 carbon i, atoms, and most preferably 1 carbon atom. The preferred ester monomer of formula (II) is vinyl acetate.
In accordance ~ith one~embodiment of the !dual : additive compositions of the present invention, the second component lubricating oil rlow improvers are one or more of ~those including (1) interpolymers of (a) i;
.s~ unsaturated esterified dicarboxylic acids or anhydrides;
, ~ . ~, . .

and (b) vinyl esters, a}pha-olefins or styrene; (2) poly-2-alkylacrylates; or (3) polyacrylates. In a - : : .

_7_ 133~ ~2 particularly preferred embodiment the second component comprises interpolymers of dialkyl fumarates and vinyl esters, in which the fumarates are esterified with mixtures of C6 through C20 alcohols.
As noted above, in a preferred embodiment, the dual additive composition of the pre~ent invention is employed in combination with a viscosity index improving amount of a viscosity modifier including a copolymer of ethylene with a higher alphà-olefin, particularly one such as propylene.
In accordance with another embodiment of the present invention, lubricating oil compositions having improved flow properties are provided comprising the above-noted dual additive composition.
DETAILED DESCRIPTION
The additives of the present invention comprise a synergistic mixture of the specified first component polymers and interpolymers of unsaturated ca:rboxy esters along with at least one second component lubricating oil flow improver.~ Th-~ critical first component of this mlYtur~ s~;a~polymer or~interpolymer of an~ acrylic acid ester having the formula~

H \ / C - OR

n which~R' is~eith-r hydrogen or the COOR radical, and ln wh1ch R is a C14 alkyl group. The production of these ~;~ : - ,.

i' -8- 1 3 3 ~
ester and diester polymers includes an esterification reaction between unsaturated mono- or dicarboxylic acids or their corresponding anhydrides, as well as the polymerization of the esterified monomers, and is well known in the art, as specifically disclosed beginning at column 2, line 35 of Cashman et al, U.S~ Patent No.
2,825,717.

The first component preferably includes the interpolymers of the diester monomers of formula (I), wherein R' is COOR, with a monomer of formula (II), preferably vinyl acetate, in a reaction which is carried out in the presence of free radical initiators, such as a peroxide catalyst.
The first component is characterized by a low molecular weight, i.e., a number average molecular weight (Mn) (as determined in the same manner as described below in connection with the second component flow improver) of not greater than about 40,000, and typically ranging from about 1,500 to about 40,0Q0, and preferably from about 2,500 to about 15,000. Corresponding specific viscosities are the same as described below in connection with the second component.
When interpolymers of monomer components depicted by form~las (I~ and (II) are employed as the first component, the mole ratio employed for the polymerization of such monomers can typically vary from about 1.3:1 to about 0.5:1, preferably from about 1.2:1 .

t, ` ~ ' -9- 1331~

to a~out 0 5 1, and most preferably from about 1 2 1 to about 1 1 Furthermore, the details with respect to conditions for esterification, homopolymerization, and interpolymerization reactions are essentially the same as set ~orth below with reference to the esterification and interpolymerization of the dicarboxylic acid esters described below in connection with the vinyl-ester-containing interpolymers of the second component hereof The synergistic combinations of the present invention include, along with these specified first component carboxy ester polymers and interpolymers, at least one second component lubricating oil -flow improver The general term ~lubricating oil flow improver" (LOFI) covers all those additives which modify the size, number, and growth of wax crystals in lube oils in such a way a- to impart improved low temperature handling, pumpability, and/or vehicle operability as measured by such tests as~ pour point and mini rotary viscometry (MRV) The ~majority of lubricatin~ oil flow improvers are ~polymer- or contaln polymers These polymers are generally of two types, either backbone or sidechain The backbone variety, such as the ethylene-vinyl~acetate- (EVA), haYe various~ lengths of methylene gment- ~randomly~di-trlbuted in~the backbone of the polymer, which~associat- or cocrystallize with the wax cry-tal- inhibitlng further crystal growth due to branches and non-crystalizable segments in the polymer r ` .

' o- ~331 ~

The sidechain type polymers, which are the predominant variety used as LOFI's, have methylene segments as the side chains, preferably as straight side chains. These polymers work similarly to the backbone type except the side chains have been found more effective in treating isoparaffins as well as n-paraffins found in lube oils. All the lubricating oil flow improvers of the second component of the present invention and as described hereinafter in connection with the second component fall into this latter category.
The lubricating oil flow improvers of the present invention generally comprise long chain ~flow improving polymers or interpolymers of the sidechain type, which contain pendent ester groups derived from a mixture of alcohols whereby the alcohol residue can be haracterized as repeating methylene units, and which are oil soluble, or dispersibl-, polymeric compositions that gene`rally have low molecular weights (number average, as determined by vapor phase osmometry or membrane osmometry), i.e., not greater than about 40,000, and typically ln the range of between about ~1,500 and 40,000, and preferably between about 2,500 and 15,000.
Alternatively, such molecular weights of the - second component lubricating oil flow improvers of the pres-nt invention are ~more conveniently expressed by the specific viscosity exhibited by such polymers.
Accordlngly,~ such spociflc viscosities will typically range from about 0.11 to about 2.2, preferably from about i :~:
~'````' ~"

D 1 1 1 3 3 1 ~ ~ 2 0.2 to about 0.9, and most preferably from about 0.2 to about o.7.
Such specific viscosities are determined in accordance with the following equation:

Specific Viscosity = K-vi_ of-~o~u-~ion _ 1 K-vis of Solvent wherein ~K-vis of Solution~ is the kinematic viscosity at 104-F (40-C) of a 2.0 mass/volume percent solution of the polymer (a.i.basis) in mixed xylenes (solvent) available commercially, using Ubbelohde-type viscometers with a viscometer constant of about 0.003 cSt/second; and the ~K-vis of Solvent~ is the corresponding kinematic viscosity of the solvent alone at the same temperature.
All speclfic viscosities reported herein are determined ~ by the above method.
; one class of such lubricating oil flow improvers includes interpolymers, preferably copolymers of certain unsaturated dicarboxy esters with certain s~ecifi-d polym-rizable monomeric compounds, namely, vinyl sters~, alpha-ol-fins, or styrene.
Suitable ethylenically unsaturated dicarboxylic acids ~or their ~ anhydridea, ~ which are ~eventually esterified, have the carboxyl or anhydride groups located on vici~al carbons~ and have 4 to 10 carbons inithe un-sterified~ monomer molecule. Suitable dicarboxylic acids or anhydrides thus ~include fumaric acid, maleic anhydrid-, mesaconic~acid~, cltraconic acid and anhydrlde, and~itaconic a~cid and~-its~anhydride.

~ -12- 133~ ~2 ~ he particular dicarboxylic acid or anhydride monomer which is preferred will depend on the identity of its comonomer. Thus, when the comonomer is a vinyl ester, the preferred dicarboxylic acid is fumaric acid.
When the comonomer i9 an alpha-olefin or styrene, the preferred dicarboxylic monomer is maleic anhydride.
Furthermore, whether it i9 preferable to esterify the dicarboxylic acid or anhydride monomer first and then interpolymerize, or to first interpolymerize the free acid or anhydride monomer and then esterify, depends on the particular identify of the dicarboxylic monomer and its comonomer.
Thus, for example, it is conventional to first esterify the fumaric acid monomer or any other dicarboxylic monomer, prior to interpolymerization with a vinyl ester.
In contrast, it is also conventional to polymerize maleic anhydride with styrene or the alpha-olefins, and to then esterify.
The nature of the alcohols used to esterify the dicarboYylic acid ~or anhydride, whether prior or subs-qucnt to interpolymerization, is the same in all instances.
Moreover, while it is preferred to achieve compl-te esterification of all of the carboxyl groups of the~dicarboxylio monomer, it is permissible to achieve only partial; esterification, of typically not less than about 70, and preferably not less than about 80, mole %
of the available esterifiable carboxyl groups.

.~. ~ . :-- ~

_ -13- 1331~5~
Accordingly, esterification is conducted with mixtures of alcohols, which alcohols can be slightly branched, preferably straight chain, most preferably straight chain alkyl Thus, the alcohols used for esterification are typically selected from the C1 to C20 aliphatic alcohol~, preferably the C6 to C20 aliphatic alcohols, and more preferably the C8 to C18 aliphatic alcohols Primary alcohols are preferred over secondary and tertiary alcohols, and the alcohols are preferably saturated, although some degree of unsaturation (i e , less than about 2 mole %) is permissible in various alcohol mixtures Straight and lightly branched chain alcohols are preferred over highly branched alcohols ,. - , The alcohols particularly selected for esterification should include sufficient hydrocarbon to , , .
~` insure oil solubility or dispersibility in the lubricating oils of the present invention, and thus m1xtures of alcohols in the C4 to C20 average carbon number range are preferred, most particularly in the C
to C18 range In a more general sense, however, it is pref-rred to utiliz-~a mixture of alcohols wherein the i molar proportion, within said mixture, of alcohols containing an average carbon number between about Cl and about C7 can typically vary from about O to about 30, pr-ferably less than about 10 mole %, based on the total numb-r~ of moles of alcohols in said mixture, and correspondingly the molar portion, within said mixture, of alcohols containing an average carbon number between about C8 and about~C18, can vary correspondingly from , .
.

-14- 1 3 ~ 2 about 100 to about 70 (e.g., 100 to 75), preferably from about 100 to about 80, and most preferably from about 100 to about 90 mole % of the alcohols in said mixture. The most preferred alcohol mixtures will have an average nùmber of carbon atoms of from 12.5 to about 13.5.
Representative examples of suitable alcohols thus include n-butanol, sec-butanol, isobutanol, n-pentanol, neopentanol, n-hexanol, octanol, isooctanol, decanol, n-dodecanol, n-tricosanol, n-tetracosanol, n-tridecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, and mixtures thereof.
As indicated above, the dicarboxylic monomer can be interpo}ymerized with a variety of different comonomers.
The first of these comonomers is a vinyl ester defined herein, to be represented by the following formula:

n whlc Rl is an ~lkvl~;r~u c aining from about 1 to 18 carbon atoms,~ preferably from about 1 to 6 carbon atoms, and most preferably 1 carbon atom, whereby the preferred ester monomer of formula ~II) is vinyl acetate.
The preferred interpolymers o~ this class of lubricating oil~rlow improvers are ~C8 to C18 dialkyl fumarate/vinyl acetate copolymers.
The mol- ~ratio of~the unsaturated dicarboxyl , ~.
~ monomer to vinyl ester in the polymerization reaction , ~

. , .

1 3 ~ 2 mixture can vary typically from about 1.3:1 to 0.5:1, preferably from about 1.2:1 to 0.7:1, and most preferably from about 1.2:1 to 1:1.
Blends of two or more different dialkyl fumarate/vinyl acetate copolymers are particularly preferred as the second component wherein each component of the blend is primarily distinguished by the carbon number of the alcohols initially employed to esterify the monomers of the individual copolymers. A preferred polymer blend is comprised of an equal weight mixture of a C8 to C18 dialkyl fumarate/vinyl acetate copolymer and a C12 to Cl8 dialkyl fumarate/vinyl acet te copolymer.
These interpolymers can be - prepared by conventional free radical polymerization techniques, starting with a mixture of all of the constituent monomers which is essentially free of polymer. Thus the polymers are random interpolymers and are not graft or block interpolymers. Conventional free radical polymerization catalysts, such as azobis-tisobutyronitrile), tert-butyl hydroperoxide, and benzoyl peroxide, can be used. Such polymerization techniques can be conducted neat in the absence of solvent or in bulk.
f, ~ ~ "
Polymerization of the ester monomers is preferably carrieù out in an inert hydrocarbon solvent, ~'- such as hexane or heptane, or low viscosity lubricating oils. Polymerization is carried out in an oxygen-free `-; reactor. The desired atmosphere can be maintained by -~ carrying out the polymerization in a nitrogen atmosphere : ~' .

-16- ~331~2 as is known in the art. Temperatures of about 65 to about 150-C, depending on the choice of initiator, can be used. Polymerization is carried out at either atmospheric or super-atmospheric pressure and on either a batch or a continuous basis. Polymerization can be stopped when the described degree of polymerization is reached by known techniques, such as adding inhibitors to the reaction mixture, or can be allowed to go to completion.
The second component lubricating oil flow improvers of this class are distinguished from the first component in that a single C14 alcohol is not employed to make the second component.
The second type of comonomer employed for interpolymerization with the unsaturated dicarboxyl monomer is an alpha-monoolefin. Straight chain a}pha-olefins are preferred over branched chain alpha-olefins.
Moreoverj if branching occurs, it is preferred that it occur at the beta-carbon, and that such branching contain not more than about 5, and preferably not more than about 2, carbons. Suitable a~pha-olefins typically contain between about 6 and 46, e.g., between about 10 and 22, ~, and preferably about 18 carbon atoms per molecule.

Mixtures of olefins may be used, e.g., a C10-C24 mixture.

Representative olefins include l-hexene, 1-heptene, 1-nonene, l-decene, l-hexadecene, l-octadecene, 1-eicosene, 1-heneicosene, 1-docosene, l-tricontene, 1-`~; tetracontene, 2-methyloctadecene, 2-ethyleicosene, and ~" mixtures thereof.

`.` .

; ; ' ' ' ? ', _ 17-" . 1331662 The mole ratio of alpha-olefin to unsaturated dicarboxyl monomer employed in the reaction mixture will typically range from about 1.2:1 to about 0.8:1, preferably from about 1.1:1 to about 0.9:1, and most preferably about 1:1.
The preferred interpolymer of this class i5 an interpolymer of l-octadecene and maleic anhydride subsequently esterified with the aforedescribed alcohols in the manner described hereinafter.
The third preferred comonomer for interpolymerization with the unsaturated dicarboxy monomer is styrene.
In forming this preferred unesterified intermediate polymer, the molar ratio of styrene to unsatur~ted dicarboxy-containing monomer (e.g., maleic anhydride) can typically vary from about 3:1 to about 1:1, preferably from about 2:1, to about 1:1, and most preferably from about 1.5:1 to about 1:1.
Most~preferably, equal molar amounts of styrene and unsaturated~ carboxy containing monomer ~e.g., maleic anhydride)~ are employed. In addition, minor amounts of other miscellan-ous interpolymorizable comonomers can be .
included in the reaction mixture. By minor amount is - ~ typically meant less than about 1, preferably less than -about 0.3 mol- of miscellaneous monomers per mole of caX oxy containing~monomor.~ Similar consideratlons, vis-a-vis- miscellaneous;monomers, apply with respect to use ,-of~ the alpha-olofins as a comonomer for interpolymerization with the dicarboxy monomer.

~ :, :: , ~..

,, ~

~ -18- 13~ 2 Various methods of polymerizing styrene or the alpha-olefins and the dicarboxy-containing monomers are known in the art and need not be discussed in detail herein. Such methods include neat and bulk polymerization technigues.
The polymerization reaction for use of either the styrene or alpha-olefin comonomers with the dicarboxy monomer is typica}ly conducted to produce an unesterified interpolymer having a number average molecular weight of less than about 25,000, preferably less than about 15,000, as determined by membrane osmometry. Upon esterification, such molecular weights will be as described generally above as well~ as the corresponding specific viscosities.
The resulting interpolymer is then esterified with an alcohol mixture of the type described above with respect to esterification of the dicarboxy monomer.
The esterification reaction can be accomplished simply by heating the dicarboxy-containing polymer and the alcohol mixture under conditions typical for effecting esterification. Such conditions usually include, for exampl-, a temperature~ of àt least about 80-C, preferably from about lOO'C to about lS0C, provided'that the temperature be below the decomposition point~ of the~ reaction ~ mixturej and the water of es~eerification~is~removed~aslthe reaction proceeds. Such conditions may;opti~onally include the use of an excess of the~alcohol reactant~so as to facilitate esterification, the use of a solvent or diluent such as mineral oil, . . ~ .
.- -~ ' , .
.,~
i~ : . .

-19- 1331~2 toluene, benzene, xy~ene or the like, and the use of an esterification catalyst such as toluene sulfonic acid, sulfuric acid, phosphoric acid, or the like. These conditions and variations thereof are well known in the art.
Another cla~s oS lubricating oil flow improvers useful in accordance with the present invention comprises the polymers and interpolymers of unsaturated mono-esters, preferably polymers of long side chain unsaturated mono-esters, and interpolymers of long and short side chain unsaturated mono-esters. The unsaturated esters are generally acrylate or 2-alkylacrylat- mono-esters represented by the formula:

~ Rl2 , (III) C = CH2 wherein R2 is hydrogen or a Cl to C5 alkyl group; and R3 is a COOR4 group wherein R4 is a Cl to C20, preferably a CIo to C18 alkyl group. A~2-alkylacrylate is one wherein R2 ~is alkyl. ; The hydrocarbyl groups constituting R4 repr-sent eh- ~hydrocarbyl resLdues of mlxtures of alcohols .rom which~th- same are prepared, which alcohols are preferably saturated, although some degree of unsatura~ion is permissible when mixtures of alcohols are mproy-d, e.g., ~leas than about 2 mole ~ of the alcohols in ~the ~mixture~can~b~e unsaturated. Straight chain or lightly ~branched- alcohols are preferred ~over highly branch-d~alcohol-. The~mixtures of alcoho}s employed are thosei~containing from Cl to about C20 carbons which can `!' ~ ' . -20- 133~ ~2 be employed in such proportions that the average number of carbons in the alcohol residue of the monomer molecule i~ preferably between about 10 and about 18.
Furthermore, it is preferred that at least 60 mole %, most pre~erably at least 80 mole % of the alcohols present in such mixture contain between 10 and 18 carbon atoms.
Representative acrylate, and C1 to C5 2-alkylacrylate monomers suitable for use in preparing the~
ester polymers and interpolymers of Formula (III), subject to the above carbon number average restrictions, include methyl acrylate, propyl methacrylate, propyl ethacrylate, octyl propacrylate, decyl butacrylate, dodecyl pentacrylate, hexyl methacrylate, octyl ethacrylate, decyl methacrylate, dodecyl methacrylate, tetradecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, tridecyl acrylate, tetradecyl ;
methacrylate, pentadecyl acrylate, hexadecyl acrylate, -~
a~d octadecyl acrylate. -~
, :
Most pref-rred acrylates or 2-alkyl acrylates are those containlnq Ci2 to C18 alkyl esters~ having a carbon number averag- of about 13 in the mixture for the alkyl (alcohol residue) portion of the ester.
' The long chain aliphatic esters are those desoribed in~Formula ;(III) wherein R4 may be prepared from mixed~aliphatlc ~a~lcohols containing from~10 to 20 carbon atoms per molecule. Saturated aliphatic a~cohols containLng; from 12 to 18 carbon atoms per molecule are preferr-d.

, ~:
.~ ~
` ~: ' -21- 133~ ~2 . .. . .
Short chain unsaturated esters, having the above-noted Formula (III), but wherein R4 has less than 10 carbons, preferably 1 to 5 carbons, in amounts of 5 to 50 molar percent, preferably 10 to 20 molar percent, based on the total polymer, can be copolymerized with the long chain unsaturated esters.
Preferably, all the alkyl esters in a given polymer will have the same acid moiety, e.g., the mixture o~ esters will be a mixture of acrylates or 2-alkylacrylates (e.g., methacrylates).
The minimum number of carbon atoms of the R4 substituent of the ester monomer is typically selected to avoid insolubility of the polymer in the lubricating oil, and the maximum number of carbon atoms therein is selected to avoid crystallizaiton of the polymer out of the lubricating oil at low temperatures.
The polymers or interpolymers of Formula ~III) are characterized by number average molecu}ar weights and specific viscosities as described above.
The polymers and interpolymers of Formula (III) can be prepared by conventional free radical ~ ~ :
polym-rization techniques, starting with a mixture of all of the constituent monomers which is essentially free of polymer. Thus, the polymers are random interpolymers and ,, .
are not graft or block interpolymers. Conventional free~ -radical polymerlzation catalysts, such as `-azobis(isobutyronitrilej, tert butyl hydroperoxide, and benzoyl .peroxide, can be used. Such polymerization `; ~ ` ' - .
:.
- .

-22- 133~62 techniques again include neat and bulk polymerization techniques.
Polymerization of the ester monomers is preferably carried out in an inert hydrocarbon solvent, such as hexane or heptane or low viscosity lubricating oil. Polymerization is carried out in an oxygen-free reactor. The desired atmosphere can be maintained by carrying out the polymerization in a nitrogen atmosphere as is known in the art. Temperatures of about 65 to about 120-C, depending on the choice of initiator, can be used. Polymerization is carried out at either atmospheric or super-atmospheric pressure and on either a batch or continuous basis. Polymerization can be stopped when the desired degree of polymerization is reached by ` known techniqu-s, such as ~addlng inhib~itors to the ~` reaction mixture, or can be allowed to go to completion.
As ls noted above, the preferred lubricating oil c~ompositions of th- prese;nt invention include a `~.``~ viscosity index~improver as an optional third component ;whlch~ s combined wlth the~ dual addltive~compositions in a~-lube oil formula~tion. ~Thus, while the dual additive ;c~ompositlon of the~present lnventlon need not be~sold in admixture with a viscosity index improvqr, the former will normally exert its desired effect in the presence of the~làtter.
Thes~ oll-soluble hydrocarbon polymeric vlscoslty Lndex~ (V~.I.) improver addltives contemplated to b-~compounded into the lubrlcating oil in accordance with thls inventlon~ ar- g-n-Fally high molecular weight -~:
..::

- -23- 1 3 31i~ ~2 .

hydrocarbon polymers. The V.I. improvers may also be derivatized to include other properties or functions, such as the addition of dispersancy properties.
These oil soluble V.I. polymers will generally have number average molecular weights of from about 40,000 to 1,000,000, preferably from about 40,000 to about 300,000, as determined by gel permeation chromatography or membrane osmometry.
Examples of suitable hydrocarbon polymers include homopolymers and interpolymers of two or more monomers of C2 to C30, e.g., C2 to C8 olefins, including both alpha-olefins and internal olefins, which may be straight or branched, aliphatic, aromatic, alkyl-aromatic, cycloaliphatic, etc. Frequently they will be of ethylene with C3 to C30 olefins, particularly preferred being the copolymers of ethylene and propylene.
other polymers can be used such as poIyisobutylenes, homopolymers and interpolymers of C6 and higher alpha-... . .
olefins, atactic polypropylene, hydroqenated polymers andcopolymers and terpolymers of styrene, e.q., with isoprene and/or butadi-ne.l More specifically, other hydrocarbon polymers suitable as viscosity index improvers in the present invention include those which may be described as hydrogenated or partially hydrogenated homopolymers~ and random, taper-d, ~star,~or block interpoIymers (including terpolymers, tetrapoly=ers, etc.) of conjugated dienes and/or monovinyl aromatic compounds with, optionally, alpha-olefins~or lower alkenes, e.g., C3 to C18 alpha-~; : , ~': ~ ' .
` ~ ' r r~

-24- 133~2 olefins or lower alkenes. The conjugated dienes include isoprene, butadiene, 2,3-dimethylbutadiene, piperylene and/or mixtures thereof, such as isoprene and butadiene.
The monovinyl aromatic compound~ include any of the fol}owing, or mixtures thereof, vinyl di- or polyaromatic compound~, e.g., vinyl naphthalene, but are pre~erably monovinyl monoaromatic compound~, such as styrene or alkylated styrenes substituted at the alpha-carbon atoms of the styrene, such as alpha-methylstyrene, or at ring carbons, such as o-, m-, p-methylstyrene, ethylstyrene, propylstyrene, isopropyl-styrene, butylstyrene, isobutylstyrene, tert-butylstyrene (e.g., p-tert-butylstyrene). Also included are vinylxylenes, methylethyl styrenes and ethylvinylstyrenes. Alpha-olefins and lower alkenes optionally included in these random, tapered and block copolymers preferably include ethylene, propylene, butene, ethylene-propylene copolymers, isobutylene, and polymers and copolymers thereof. As is a1so known in the art, these random, tapered and block copolymers may include relatively small amounts, that is less than about 5 moles, of other copol y erizable~monomers such as vinyl pyridines, vinyl lactams, methacrylates, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl stearate, and the like.
Specific ~exampl-s include random polymers of butadiene and/or~isoprene~and poIymers of isoprene and/or butad1ene and~ styren-. Typlcal block copolymers include polystyrene-polyisoprene, polystyrene-polybutadiene, polystyrene-polyethyl-ne, polystyrene-ethylene propylene ~;
.
~ .
. ~ ~

~J -2S-` ``` 133~
copolymer, polyvinyl cyclohexane-hydrogenated polyisoprene, and polyvinyl cyclohexane-hydrogenated polybutadiene. Tapered polymers include those of the foregoing monomers prepared by method~ known in the art.
Star-shaped polymers typically comprise a nucleus and pclymeric arms linked to said nucleus, the arms being comprised of homopolymer or interpolymer of said con~ugated diene and~or monovinyl aromatic monomers.
Typically, at least about 80% of the aliphatic unsaturation and about 20% of the arcmatic unsaturation of the star-shaped polymer is reduced by hydrogenation.
Representative examples of patents which disclose such hydrogenated polymers or interpolymers include U.S. Patent Nos. 3,312,621; 3,318,813: 3,630,905;

3,668,125: 3,763,044: 3,795,615; 3,835,053; 3,838,049;

3,965,029; 4,358,565; and 4,557,849.

The polymer may be degraded in mo}ecular weight, for example by mastication, extrusion, oxidation or thermal degradation, and it- may be oxidized and : -contain oxygen. Also included are derivatized polymers such as post-grafted interpolymers of ethylene-propylene with an active monomer such as maleic anhydride which may be further reactlèdlwith an alcohol, or amine, e.g., an alkylene polyamine or hydroxy amine , e.g., see U.S.
Patent Nos. 4,089,794; 4,160,739: 4,137,185; or copolymers of ethylene and propylene reacted or grafted with nitrogen compounds such as shown in U.S. Patent Nos.

4,068,056; 4,068,058: 4,146,489; and 4,149,984.
.~.;
~ .

~ 26- 13~ 2 Suitable hydrocarbon polymers are ethylene interpolymers containing from 15 to 90 wt. ~ ethylene, preferably 30 to 80 wt. % of ethylene and 10 to 85 wt. %, preferably 20 to 70 wt. ~ of one or more C3 to C8, alpha-olefins. While not essential, such interpolymers preferably have a degree of crystallinity of less than 10 wt. ~, as determined by X-ray and differential scanning calorimetry. Copolymers of ethylene and propylene are most preferred. Other alpha-olefins suitable in place of propylene to form the copolymer, or to be used in combination with ethylene and propylene, to form a terpolymer, tetrapolymer, etc., include l-butene, 1-pentene, l-hexene, l-heptene, l-octene, etc.: also branched chain alpha-olefins, such as 4-methyl-1-pentene, 4-methyl-1-hexene, 5-methylpentene-1, 4,4-dimethyl-1-pentene, and 6-methyl-heptene-1, etc., and mixtures thereof.
Terpolymers, tetrapolymers, etc., of ethylene, said C3-8 alpha-olefin, and a non-conjugated diolefin or mixtures of such diolefins may also be used. The amount i~ ~
;~ of the non-conjugated diolefin qenerally ranges from about 0.5 to 20 mole percent, preferably from about 1 to --.,~ .
about 7 mole percent, based on the total amount of ethylene and alpha-olefin present.
Th- lubricating oiI compositions of the present invention employ a base oil which may be either natural base oil, or a mixture of natural and synthetic base oils.

:
' .'`~

~` -27- 1331~62 Thus~ base oils suitable for use in preparing the lubricating compositions of the present invention include those conventionally employed as crankcase lubricating oils for spark-ignited and compression-ignited internal combustion engines, 5uch as automobile and truck engines, marine and railroad diesel engines, and the like. Advantageous results are also achieved by employing the dual additive composition of the present invention in base oils conventionally employed in and/or adapted for use as power transmitting fluids such as automatic transmission fluids, tractor fluids, universal tractor fluids and hydraulic fluids, heavy duty hydraulic fluids, power steering fluids and the like. Gear lubricants, industrial oils, pump oils and other lubricating oil compositions can also benefit from the - ~
incorporation therein of the additives of the present invention.
- Thus, the dual additive composition of the present invention may be suitably incorporated into mixtures of natural~and~ synthetic base oils, provided the-- mixtur-s lnclud- at least about 80% of the natural bas-~oil. Suitabl-~synthetic base olls for use in these mixtures include alkyl esters of dicarboxylic acids, polyglyc!ols and alcohols, polyalphà-olefins, polybutenes, alkyl benzenes, ~ organlc sters of phosphoric acids, polysillcone~oils,; tc.
Natural~bas-~oil- include mineral lubricating oils ~which may vary widely as to their crude source, e.g., whether paraffinic, naphthenic, mixed, paraffinic-. ~,,: .~

~ -28- 133~ ~2 .
naphthenic, and the like; as well as to their formation, e.g., distillation range, straight run or cracked, hydrofined, solvent extracted and the like.
More specifically, the natural lubricating oil base stocks which can be used in the compositions of this invention may be straight mineral lubricating oil or distillates derived from paraffinic, naphthenic, asphaltic, or mixed base crudes, or, if desired, various blends of oils may be employed as well as residuals, particularly those from which asphaltic constituents have been removed. The oils ~ay be refined by conventional methods using acid, alkali, and/or clay or other agents such as aluminum chloride, or they may be -xtracted oils produced, for example, by solvent extraction with solvents of the type of phenol, sulfur dioxide, furfural, dichlorodiethyl ether, nitrobenzene, crotonaldehyde, etc.
The lubricating oil base stock convenient}y has a viscosity of typically about 2.5 to about 12, and preferably about 2.5~to about 9 cs. at 100C.
Thus, the dual addi-tive composition of the present ;invention~can be employed in a lubricating oil composition which comprises lubricating oil, typically in a ma~or amount, and,~ t~he dual additive composition, typically in a minor amount, which is effective to impart the ~ enhanced f1ow ~properties described herein.
Additlonal conyentional addltives selected to meet the par~ticular requiremenes of a selected type of lubricating oil composition can be included as desired.

,i.

:.. i.!':.: !: ., ." . j 1331~6~
The dual additive compositions of this invention are oil-soluble, dissolvable in oil with the aid of a suitable solvent, or are stably dispersible materials. oil-soluble, dissolvable, or stably disp~rsible as that terminology is used herein does not necessarily indicate that the materials are soluble, dissolvable, miscible, or capable of being suspended in oil in all proportions. It does mean, however, that the dual additive composition, for instance, is soluble or stably dispersible in oil to an extent sufficient to exert its intended effect in the environment in which the oil is employed. Moreover, the additional incorporation of other additives may also permit incorporation of higher levels of a particular dual additive composition hereof, if desired.
Accordingly, while any effective amount of the dual additive composition can be incorporated into the final, e.g., fully formulated, lubricating oil composition, it is contemplated that such effective amount be sufficient to provide said lube oil composition with an amount of the dual additive composition of typiqally from about O.OOS to about 0.7, e.g., 0.02 to 0.5, and preferably from 0.05 to 0.3 wt. percent, based on the weight of said lubricating composition.

With respect to the second component (i.e., lube oil flou improver), it is contemplated that effective amounts thereof in the final lubricating oil composition will typically range from about 0.003 to 0.54, e.g., from about 0.013 to 0.36, and preferably from ~'~
.

, ' i' . ~ ~ . ; ' ' ' " : ~' ~30- 1331 ~62 about 0.03 to 0.033 wt. %, based on the weight f said composition.
The amount of the first component in the final lubricating oil composition is conveniently based on the amount o~ second component in that final composition.
Accordlngly, it is contemplated that e~fective weight ratios of the second component to the first component will typically range from about 1/0.3 to 1/0.9, preferably from about 1/0.4 to 1/0.6, and most preferably about 1/0.5. In other words, in a moct preferred embodiment there will be one-half as much of the first component as the second component present in the final composition.
The optional third component, i.e., the V.I.
improver, will typically be employed in the final lubricating oil composition in amounts of from about 0.6 to 2.8 wt. %, with the precise amount being selected on the basis of the particular type of lubricating oil being :, , . :, .
e~ployed.
Th- dual additlve composition of the present invention can be incorporated into the lubricating oil in any convenient way. Thus, it can be added directly to the oil by dispersing, or dissolving the same in the oLl at the desired level of concentration. Such blending can occur at rcom temperature or elevated temperatures.
Alternatively, the dual additive composition may be blended with a base oil to form a concentrate, and the ~ r ;~ concentrate then blended with lubricating oil base stock to obtain the final composition. Such concentrates will ~.

,~ ' .

-31- 1331~2 typically contain the dual additive composition in amounts of from about 2.0 to about 90, and preferably from about 40 to 65 percent, by weight, based on the concentrate weight. The concentrate can also include the optional third component, or V.I. improver.
The lubricating oil base stock for the dual additive composition of the present invention typically is adapted to perform a selected function by the incorporation of additives therein to form lubricating oil compositions designated as formulations.
Representative additives typically present in such formulations include corrosion inhibitors, oxidation inhibitors, friction modifiers, dispersants, anti-foaming agents, anti-wear agents, detergents, rust inhibitors and the like.
Corrosion inhibitors, also known as anti-corrosive agents, reduce the degradation of the metallic parts contacted by the lubricating oil composition.
I~lustrative of corrosion inhibitors are phosphosulfurized hydrocarbons and the products obtained by reaction of a phosphosulfurized hydrocarbon with an alkallne earth~ metal oxlde or hydroxide, pr-ferably in the presence of an alkylated phenol or of an alkylphenol thioester, and also preferably in the presence of carbon dioxide. Phosphosulfurized hydrocarbons are prepared by reacting a suitable~;hydrocarbon such as a terpene, a .: .
` h-avy petroleum~fraction of a C2 to C6 olefin polymer such as~polylsobutylene, with from 5 to 30 wt. percent of ~--a sulfide of phosphorus for 1/2 to 15 hours, at a ~ :
'`'~ ' ... .
. ~ .

_ _ -32- 1331~2 temperature in the range of 150 to 600F.
Neutralization of the phosphosulfurized hydrocarbon may be effected in the manner taught in U.S. Patent No.

<?/ .: :.`
~,969,324.
Oxidation inhibitors reduce the tendency of mineral oils to deteriorate in service which deterioration can be evidenced by the products of oxidation such as sludge and varnish-like deposits on the metal surfaces, and by viscosity growth. Such oxidation ~;
. . ...
inhibitors include alkaline earth metal salts of alkylphenolthioesters having preferably C5 to C12 alkyl side chains, e.g., calcium nonylphenol sulfide, balrium ~ ;
t-octylphenyl sulfide, dioctylphenylamine, phenylalpha- -,, . naphthylamine,- phospho- su}furized or sulfurized hydrocarbons, etc.
Friction modifiers serve to impart the proper - . .
friction charaateristics ~eo lubricating oil compositions such as.automatic transmission f}uids. ~ --Repres-ntative examples ~of sultable friction modlfiers are found~ n~;U.S~. Patent No. 3,933,6s9 which disaloses~ fatty~ acld~esters ~nd amides; U.S. Patent No.
4,176~,074 which desarlbes molybdenum camplexes of polyisobutyenyl succinic anhydride-amino alkanols; U.S
Patent No. 4,105,571 which discloses glycerol esters of dime~rized ~fatty~ acids'~U.S. Patent No. ~3,779,928 which dlsclases;~ alkane phosphonia aaid~ salts; U.S. Patent No.
3,~778,375 which discloses reaction products of a phosphonate wlth an oleamide; U.S. Patent No. 3,852,205 which discloses~ S-carboxyalkylene hydrocarbyl ,. . .
. :

-33- 133~2 succinimide, S-carboxyalkylene hydrocarbyl succinamic acid and mixtures thereof; U.S. Patent No. 3,879,306 which discloses N-~hydroxyalkyl)alkenyl-succinamic acids or succinimides; U.S. Patent No. 3,932,290 which discloses reaction products of di- (lower alkyl) phosphites and epoxides; and U.S. Patent No. 4,028,258 which discloses the alkylene oxide adduct of phosphosulfurized N-~hydroxyalkyl) alkenyl succinimides.
The most preferred friction modifiers are succinate esters, or metal salts thereof, of hydrocarbyl substituted succinic acids or anhydrides and thiobis alkanols such as described in U.S. Patent No.
4,344,85~.
Dispersants maintain oil insolubles, resulting from oxidation during use, in suspension in the fluid .

thus preventing sludge flocculation and precipitation or deposition on metal parts. Suitable dispersants include high molecular weight alkyl succinates, the reaction product of oil-soluble polyisobutylene succinic anhydride . . .
with ethylene amines such as tetraethylene pentamine and ~ borated salts thereof.

``~ Foam control can ~e provided by-an antifoamant ` of the polysiloxane type, e.g., silicone oil and ~ polydimethyl sil!oxane.i`" ` !

`~ Anti-wear agents, as their name implies, reduce , . . .
~-~ wear of metal parts. Representatives of conventional anti-wear agents are zinc dialkyldithiophosphate and zinc diaryldithiosphate. -'` ' ;~ ~

~ ....
`:

;; 133l~2 Detergents and metal rust inhibitors include the metal salts of sulphonic acids, alkyl phenols, sulfurized alkyl phenols, alkyl salicylates, naphthenates and o.her oil soluble mono- and di-carboxylic acids.
Highly basic (viz, overbased) metal salts, such as highly basic alkaline earth metal sulfonates (especially Ca and Mg salts) are frequently used as detergents.
Representative examples o~ such materials, and their methods of preparation, ~re found in Canadian Patent 1,262,721.
Some of thes~ numerous addltives can provide a multiplicity of effects, e.g.,` a dispersant-oxidation inhibitor. This approach is well ~nown and need not be further elaborated herein.
Compositions when containing these conventional additives are typically blended into the base oil in amounts which are effective to provide their normal at~tendant function. Representative effective amounts of such additives are illustrated as follows:

- % Active Inaredient By Add~ ye Volume Weight .. ,....................................................................... -Corrosion Inhibi~or 0.01-1 0.01-1.5 Oxidation Inhibitor 0.01-1 0.01-1.5 Dispersant 0.1-~ 0.1-8 Anti-Foaming Agents 0.001-0.1 0.001-0.15 Anti-Wear Agents 0.001-1 0.001-1.5 -~ Friction ~odifiers j l ! 0~Ol-l' i 0.01-1.5 Detergents/Rust Inhibitors 0.01-2.5 0.01-3 Mineral Oil Base Balance Balance -~ ~ When oth-r additives are employed, it may be desirable, although not necessary, to prepare additive ,.. :: - , ~ concentrates comprising concentrated solutions or . -35-dispersions of the dual additive compos~t2ion (in concentrate amounts hereinabove described), together with one or more of said other additives (said concentrate when constituting an additive mixture being referred to herein as an additive-package) whereby several additives can be added simultan~ously to the base oil to form the lubricating oil composition. Dissolution of the additive concentrate into the lubricating oil may be facilitated by solvents and by mixing accompanied with mild heating, but this is not essential. The concentrate or additive-package will typically be formulated to contain the dual additive composition and optional additional additives in proper amounts to provide the desired concentration in .
the final formulation when the additive-package is combined with a predetermined amount of base lubricant.
Thus, the dual additive composition of the present invention can be added to small amounts of base oil or other .compatible .solvents along with other desirable additives to form additive-packages containing active ingredients in collective amounts of typically from about 2.5 to about 90%, and preferably from about 5 to about 7S%, and most preferably:from about 8 to about so% by weight additives in the appropriate proportions ! with the remainder being base oil.
The final formulations may employ. typically about 10 wt. % of the.additive-package with the remainder being base oi}.:

All of said weight and volume percents ~ ~.
~ expressed herein are based on active ingredient (a.i.) , ~ .

content of the additive, and/or upon the total weight of any additive-package, or formulation which will be the sum of the a.i. weight of each additive plus the weight of total oil or diluent.
The following examples are given as specific illustrations of the c1aimed invention. It should be understood, however, that the invention is not limited to the specific details set forth in the examples~ All parts and percentages in the examples, as well as in the remainder of the specification, are by weight unless otherwise specified.
Comparative Example 1 A fully formulated (except for a LOFI) 15W-40 lubricating base oil (designated Base Oil A) was prepared containing mineral oil base stock oil (i.e., a mixture of 500N and 150N), V.I. improver, and a conventional detergent/inhibitor package containing ashless dispersant, anti-oxidant and anti-wear additive, and .
; overbased sulfonate. The V.I. improver was present in ~-Base Oil A in an amount of about 2 wt. % (a.i.) and i,: .
comprised ethylene-propylene copolymer masticated to a T.E. of about 1.8 + 0.01, and had a weight average :`: `
molecular weight of about 180,000 and a ratio of weight average molecular weight to number average molecular ; weight of 3.5. The copolymer had an ethylene content of 43 wt. %.

~ ~Thickening Efficiency (T.E.) is defined as the -~ ratio of the weight percent of a polyisobutylene (sold as . ::
an oil solution by Exxon Chemical Co. as Paratone N), ` . ~ *Trade mark .

- . -37-133~2 having a Staudinger Molecular Weight of 20,000, required to thicken a solvent-extracted neutral mineral lubricating oil, having a viscosity of 150 SUS at 37.8 C, a viscosity index of 105 and an ASTM pour point of 0~F, (Solvent 150 Neutral) to a viscosity of 12.4 centistokes at 98.9-C, to the weight percent of a test copolymer required to thicken the same oil to the same viscosity at the same temperature. T.E. is related to Mn and is a convenient, useful measurement for formulation of lubricating oils of various grades.
To Base Oil A was added (in the amount shown at TABLE 2) a lube oil flow improver, designated LOFI A, comprising a 50:50 weight mixture of a two-component blend of two different dialkyl fumarate/vinyl acetate copolymers, namely Component A and Component B. For Components A and B the fumarate monomer was esterified with a mixture of alcohols having the approximate -:
respective carbon distributions shown at TABLE l. ;~

` TABLE l CARBON DISTRIBUTION OF ALCOHOLS
USED TO ESTERIFY THE F~RATE OF: ~:

- Carbon Component A Component B
Number wt. % wt. %

9 I ' I ' ,! i ~ , 12`
.~` 10 -- 11 2 ~ 57 44 ~: -: 16 : 10 9 ~
: 18 11 7 ~-19 - - ~
~; ~
`~ ~r~ *Trade mark X .;_ . .S L
, ~a, I
```~''``` ~ '`' -38- 1331~2 . The specific viscosity of the polymer blend constituting LOFI A was 0.27, and the fumarate:vinyl acetate mole ratio employed in the synthesis of both Components A and B was 1:0.8.
Comp~rative,~ample 2 Comparative Example l was repeated, except that a different 15W-40 mineral oil base stock was employed.
The base oil, fully formulated in accordance with Comparative Example 1 (exclusive of LOFI), was designated Base Oil B and contained the same type and amount of - ' .
conventional additives as Base Oil A of Comparative Example 1. To Base Oil B was then added LOFI A, in the amount shown at TABLE 2.
" Compa~ative ~xa~ples 3 and 4 Comparative Examples l and 2 were again repeated, with the exception that LOFI A was replaced w1th LOFI B in the amounts shown at TABLE 2. LOFI B was a dialkyl fumarate/vinyl acetate copolymer having a specific viscosity of about 0.25 and in which the alkyl :~ :
,~ groups were derived solely from a C14 alcohol. The vinyl acetate/fumarate mole ratio in the polymerization mixture was between 0.80 and 0.85:1. Thus, LOFI B was added to Base Oil A (Comparative Example 3), and LOFI B was added to Base Oil B (Comparative Example 4).
Examp~es 1 and 2 ~`"~ To Base Oil A (for Example 1), and Base Oil B
; (for Example 2) was added a mixture of LOFI A and LOFI B
in the amounts shown at TABLE 2. The resulting `` ~`

~39~ 1331~62 formulations were tested by the MRV procedure, and the results are summarized in TABLE 2.
Exam~lçs 3 and 4 Examples 1 and 2 were repeated with the exception that LOFI A was employed in a lower amount, as i9 shown in TABLE 2.
The resulting formulation~i from Comparative Examples 1 to 4 were then also tested by the MRV
procedure described below, and the results are summarized at TABLE 2.
TABL~E 2 TEST RESULTS
EX. OR ADDITIVE VIS
COMP. BASE AMOUNTYS (PASCAL
EX. NQ. OIL ~YEE~ (WT.%)fPASCALS~ SECONDS) Comp. Ex. 1 ~ A LOFI A 0.14 ~ -solid------- ~
Comp. Ex. 2 B LOFI A 0.14 -------solid-------Comp. Ex. 3 A LOFI B 0.06~500 320 Comp. Ex. 4 B LOFI B 0.06 -------solid-------~: .
: LOFI A 0.14 Ex. 1 A + ~35 141 LOFI B 0.06 j LOFI A 0.14 Ex. 2 B + ~35 131 LOFI B 0.06 LOFI A 0.07 - ~ Ex. 3 ;!A~ LOFI IB 0.06 140 Ex. 4 LOFI A 0.07 147 LOF} B 0.06 ~= ~ Targets for SAE~lSW-40 Oil <35 300 MAX

*LOFI A Y C8-C18 dialkyl fumarate/vinyl acetate ~ LOFI B - C14 dlalkyl fumarate/vinyl acetate '., ~`.

`;'; ' ' ~ '`' ' _40_ 1 331 ~ ~2 ; ` ,.
The analysis of the flow properties of the above-described lubricating oil compositions (both comparative and exemplary) was conducted by testing the same in a Mini Rotary* Viscometer after subjecting each smaple to a temperature profile controlled in accordance with ASTM D4684 over a 44-hour cooling cycle. More specifically, this test is used by the SAE (J300 Specification) for determining the low temperature pumpability of a crankcase oil. In the test procedure itself, the temperature is gradually lowered to -20C, and then at that temperature the yield stress (YS) is measured in pascals, and the apparent viscosity (VIS) is measured in pascal seconds. The latter is required because this is a two-phase system, so that a true viscosity measurement cannot be made. Thus, in accordance with SAE requirements for 15W-40 oils, the ; target values of less than 35 pascals (YS) and not greater than 300 pascal seconds (VIS) are consldered acceptable iD order to provide a pumpable composition at ~--20C, i.e., to maintain fluidity.

These results clearly demonstrate the ,~
synergistic nature of the dual additive mixtures of the present invention. The cooling cycle of the compositions including only LOFI~ A or LOFI B above are well below the target va}ues, so as to adversely effect the viscosity of these~compositions. ~-Comparative Exam~les 5 to 8 .
In a further series of similar tests, to ~-different samples of Base oil B, fully formulated as in *$rade mark ,~ ,t,:,~", ` ,:,.. ~. ..

`` -41- 133~662 . . .
Comparative Examples 2 and 4, and using the same V.I.
improver as described therein, but without any LOFI, was then added a variety of different commercial lubricating oil flow improvers, including one based on a polymethacrylate (LOF~ C), one based on a polyacrylate (~OFI D) and one based on a styrene-maleic anhydride copolymer (LOFI E). A run using LOFI A as described in Comparative Example 1 was also conducted.
More particularly, LOFI C was a polyalkyl methacrylate composition having a specific viscosity of 0.43, which was derived from a mixture of alcohols approximately as is set forth in TABLE 3 below-CARBON DISTRIByTIoN

Carbon Number Wt.

, 15 12 9 ~4 LOFI D was a polyacrylate composition having a ~-specific viscosity of 0.14, which was based upon a mixture of alcohols approximately as is set forth in TABLE;4 below: ~ -. :
,. .
, : .
`:`:

~ -42- 13~1662 CARBON DISTR~U~O~
Carbon Number Wt. %

LOFI E was a styrene-maleic anhydride copolymer having a specific viscosity of 0.70 derivatized with a mixture of alcohols approximately as set forth in TABLE 5 ;
below:
. .
TAB~
CARBON ~ISTRI~UT~Q~
- Carbon Number~ Wt. %
~'~;: ; : ; '.
12 Sl ~'~ 13 ' ;~ 14 ~ 25 6 ~ 14 ~ ~`
8 ~ 7 ~

The amount~;of each LOFI added is shown in TABLE
6. The results of MRV testing procedure are set forth in TABLE 6 ~elow.
; Exa~ les~s~ o~8~
Comparative~Examples~5 to 8 were repeated, with --the~exception~that~LOFI ~B, as described in connection With Comparative~Exampl- 3~, ~was also added to the Base oil 3~In thé mount- ~shown at TABLE 6. The resulting ~ 43- 133~62 formulations were tested by the MRV procedure, and the results are summarized in Table 6.

TES~ RESUL~S
EX. OR ADDITIVE VIS
COMP. BASE AMOUNT YS (PASCAL
EX. NO. OIL TYPE* ~WT.%) ~PASCALSl S~CO~DS) Comp. Ex. 5 B LOFI C 0.15 -------solid-------Ex. 5 B LOFI C/ 0.15/
LOFI 3 0.06 <35 145 Comp. Ex. 6 B LOFI D 0.15 -------solid-------Ex. 6 B LOFI D/ 0.15/
- LOFI B 0.06~105 960 ~
Comp. Ex. 7 B LOFI E 0.15 -------solid------- -Ex. 7 B LOFI E/ 0.15/c35 140 LOF} B 0.06 Comp. Ex. 8 B LOFI A 0.15 -------solid-------Ex. 8 B LOFI A/ 0.15/
LOFI B 0.06 <35 138 ; Targets for SAE 15W-40 Oil ~35 300 MAX
*LOFI A - C8-C18 dialkyl fumarate/vinyl acetate LOFI B - Cl d~alkyl fumarate/vinyl acetate ~OFI C = po~ymethacrylate ` LOFI D s polyacrylate '~ LOFI E - esterified styrene/maleic copolymer -~
The resu}ts further demonstrate the synergistic nature of various dual ~additive compos'itions in ` accordance with the pres,ent invention, that is with the ~` ~ first component-i~in~ comb'inatioh 'with various different ~r'~ lube oil flow~ improvers comprising the second component thereof. It will be observed that while the formulation of Example 6~ d~id not~pass the target values of this test, the dual additive combination did result in a substantial ; -.. .. ~ .
~ improvem-nt in performance relative to LOF} D

; ~ ~ , .. ....
~ ~ .
.j .
:`
~ .
~ ~ .
. ~ ' .

~~` -44- 133~ ~2 (Comparative Example 6) above. The use of higher amounts of the dual additive composition would be expected to result in a pass.
Com~arative Examples ~-11. and Exam~le 9 In order to more clearly demonstrate the criticality of the specific first component of the dual additive composition of the present invention, further tests were conducted in order to compare its use with that of compositions with other similar materials. Thus, a Base Oil C, fully formulated as described in connection with Base Oil A of Comparative Example 1, and including V.I. improver, but not including any LOFI, was prepared.
To Base Oil C was added LOFI A, as described in connection with Comparative Example 1, in an amount as shown at TABLE 7 for Comparative Example 9.
In addition, several different dialkyl fumarate/vinyl acetate LOFI's were prepared which differed only in the number of carbon atoms in the dialkyl groups thereof, namely, LOFI's F through G.
Thus, each different LOFI was derived from a single and different alcohol having the following number of carbon . . . .
`~ atoms:

Alcohol Carbon No.
~"

~ LOFI H 16 ,:

.:

ir~,.... . . . . .

,~ ~45~ ~33~f62 To different samples of Base Oil C were added LOFI A and one of LOFI's F through H, in the amounts as shown in TABLE 7 , , Each of the above-described formulations was tested by the MRV procedure, and the results are summarized in TA~LE 7 TAB~

TEST RESULTS _ EX OR `, ADDITIVE VIS
COMP BASE AMOUNT YS (PASCAL
EX NO OIL ~ (WT ~ (PASCALS~ SE~ON~S) ~-Comp Ex 9 C LOFI A 0 14>175 solid Comp Ex 10 C LOFIs A/F 0 07/>175 solid Ex 9 C LOFIs A/G 0 07/C35 155 Comp Ex 11 C LOFIs A/H 0 07/>175 solid -~

Targets for SAE 15W-40 Oil <35 300 MAX

These results further dramatically demonstrate the criticality of using the specific C14 dialkyl .
fumarate/vinyl acetate ~first, component in ths dual additi~ve composition~of the present invention Although ~the invention herein has been described with reference to particular embodiments, it is to ~be ~nde,rstoad Ithat l~these embodiments are merely illustrative of the principles and applications of the present invention ~ It i- therefore to be understood that numerous modificatlons may~ be made to the illustrative embodiments~and; tha~t ~other arran~ements may be devised . ~:
,f~

~ 46- ~ 33~2 without departing from the spirit and scope of the ~.
present invention as defined by the appended claims.
, . ~ .

` !:
` ~' ` :~ ` : `, `

Claims (85)

1. A composition capable of improving at least the low temperature flow properties of a lubricating oil composition containing a Viscosity Index Improver, comprising, as a first component at least one low molecular weight polymer or interpolymer of unsaturated carboxy ester having the formula:

(I) wherein R' is selected from the group consisting of hydrogen and COOR and wherein R is a C14 alkyl group, and as a second component at least one lubricating oil flow improver comprising low molecular weight non-ethylene containing polymer or interpolymer containing pendent ester groups, and characterized by the presence within its structure of side chains of repeating methylene units derived from a mixture of alcohols

2. The composition of claim 1, wherein said second component lubricating oil flow improver is at least one member selected from the group consisting of (a) polyacrylates (b) poly-2-alkylacrylates, and (c) interpolymers comprised of esterified C4 to C10 monoethylenically unsaturated dicarboxylic acid or anhydride and a comonomer selected from the group consisting of vinyl ester C6 to C46 alpha-olefin, and styrene.

3. The composition of Claim 1 wherein said first component is interpolymer of dicarboxy ester of Formula (I), wherein R' is COOR and vinyl ester represented by the formula:
(II) wherein R1 comprises an alkyl group containing from 1 to 18 carbon atoms.

4. The composition of claim 3 wherein said vinyl ester comprises vinyl acetate.

5. The composition of Claim 3 wherein said second component is polymer or interpolymer of unsaturated mono-ester represented by the formula:

(III) wherein, R2 is hydrogen or C1 to C5 alkyl, and R4 is C1 to C20 alkyl, with the proviso that the average number of carbon atoms in the groups constituting R4 in the polymer or interpolymer is from about 10 to about 18.

6. The composition of claim 3 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester, and said second component is interpolymer of dialkyl fumarate and vinyl ester, wherein the alkyl portions of said dialkyl fumarate of said second component are derived from a mixture of alcohols.

7. The composition of claim 6 wherein the alkyl portions of said dialkyl fumarate of said second component interpolymer are derived from a mixture of alcohols having an average carbon number from about 4 to about 20.

8. The composition of claim 7 wherein said average carbon number is from about 8 to about 18.

9. The composition of claim 6 wherein the mole ratio of dialkyl fumarate and vinyl ester used in preparing the interpolymers of said first and second components is from about 1.3:1 to 0.5:1.

10. The composition of any one of claims 6 to 9 wherein said vinyl ester employed for both said first and second component is vinyl acetate.

11. The composition of claim 3 wherein said second component is interpolymer comprised of (a) esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons, and (b) at least one C6 to C46 alpha-monoolefin.

12. The composition of claim 11 wherein in said interpolymer of said second component, said esterified dicarboxylic acid or anhydride is derived from maleic anhydride.

13. The composition of claim 12 wherein in said interpolymer of said second component said esterified dicarboxylic anhydride is esterified with a mixture of alcohols having an average carbon number of from about 4 to about 20.

14. The composition of claim 13 wherein said average carbon number is from about 8 to about 18.

15. The composition of claim 12 wherein said alpha-olefin contains between about 10 and about 22 carbon atoms, and the mole ratio of alpha-olefin to maleic anhydride in the reaction mixture used to prepare the interpolymer of said second component is about 1.2:1 to about 0.8:1.

16. The composition of claim 11 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester, and the mole ratio of said dialkyl fumarate and vinyl ester in the reaction mixture used to prepare said interpolymer is from about 1.3:1 to about 0.5:1.

17. The composition of any one of claims 11 to 16 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl acetate.

18. The composition of claim 3 wherein said second component is interpolymer comprised of (a) esterified C4 to C10-monoethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons and (b) styrene.

19. The composition of claim 18 wherein said second component is a styrene esterified maleic anhydride interpolymer.

20. The composition of claim 19 wherein in said interpolymer of said second component the esterified portion thereof is derived from a mixture of alcohols having an average carbon number of from about 4 to about 20.

21. The composition of claim 20 wherein said average carbon number is from about 8 to about 18.

22. The composition of claim 20 wherein the mole ratio of styrene to maleic anhydride in the reaction mixture used to prepare said second component interpolymer is from about 3:1 to about 1:1.

23. The composition of claim 18 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester and the mole ratio of said dialkyl fumarate and vinyl ester in the reaction mixture used to prepare said interpolymer is from about 1.3:1 to about 0.5:1.

24. The composition of any one of claims 18 to 23 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl acetate.

25. The composition of claim 3 wherein the number average molecular weight of said first and second components is from about 1,500 to about 40,000.

26. The composition of claim 3 in combination with a viscosity index improver comprising high molecular weight hydrocarbon polymer.

27. The composition of claim 26 wherein said viscosity index improver has a number average molecular weight of between about 40,000 and 300,000.

28. The composition of claim 26 wherein said viscosity index improver comprises a compound selected from the group consisting of the polymers and interpolymers of C2 to C30 olefins.

29. The composition of claim 28 wherein said viscosity index improver comprises interpolymer of ethylene and C3 to C30 olefin.

30. The composition of claim 29 wherein said C3 to C30 olefin comprises propylene.

31. The composition of claim 26 wherein said viscosity index improver comprises a compound selected from the group consisting of the hydrogenated and partially hydrogenated homopolymers and interpolymers of conjugated dienes and/or monovinyl aromatic compounds.

32. The composition of claim 3 wherein the weight ratio of the amount of said second component to the amount of said first component in said composition ranges from about 1:0.3 to about 1:0.9.

33. The composition of claim 32 wherein the weight ratio of the amount of said second component to the amount of said first component in said composition ranges from about 1:0.4 to about 1:0.6.

34. A lubricating oil composition comprising lubricating oil, and a dual additive composition in an amount effective to improve, relative to the absence of one or more components of said dual additive composition, at least the low temperature flow properties of said lubricating oil composition when also containing viscosity index improver, said dual additive composition comprising, as a first component at least one low molecular weight polymer or interpolymer of unsaturated carboxy ester having the formula:

(I) wherein R' is selected from the gorup consisting of hydrogen and COOR, and wherein R is a C14 alkyl group, and as a second component at least one lubricating oil flow improver comprising low molecular weight non-ethylene-containing polymer or interpolymer containing pendent ester groups, and characterized by the presence within its structure of side chains of repeating methylene units derived from a mixture of alcohols.

35. The lubricating oil composition of claim 34, wherein said second component lubricating oil flow improver is at least one member selected from the group consisting of (a) polyacrylates, (b) poly-2-alkyl acrylates, and (c) interpolymers comprised of esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride and comonomer selected from the group consisting of vinyl ester, C6 to C46 alpha-olefin, and styrene.

36. The lubricating oil composition of claim wherein said lubricating oil has a viscosity of between about 2.5 and about 12 cs. at 100°C.

37. The lubricating oil composition of Claim 35 wherein said first component is interpolymer of dicarboxy ester of Formula (I) wherein R' is COOR and vinyl ester represented by the formula:

(II) wherein R1 comprises an alkyl group containing from 1 to 18 carbon atoms.

38. The lubricating oil composition of claim 37 wherein said vinyl ester comprises vinyl acetate.

39. The lubricating oil composition of Claim in combination with a viscosity index improver comprising a high molecular weight hydrocarbon polymer.

40. The lubricating oil composition of claim 39 wherein said viscosity index improver has a number average molecular weight of between about 40,000 and 300,000.

41. The lubricating oil composition of claim 39 wherein said viscosity index improver comprises a compound selected from the group consisting of the polymers and interpolymers of C2 to C30 olefins.

42. The lubricating oil composition of claim 41 wherein said viscosity index improver comprises interpolymer of ethylene and C3 to C30 olefin.

43. The lubricating oil composition of claim 42 wherein said C3 to C30 olefin comprises propylene.

44. The lubricating oil composition of claim 39 wherein said viscosity index improver comprises a compound selected from the group consisting of the hydrogenated and partially hydrogenated homopolymers and interpolymers of conjugated dienes and/or monovinyl aromatic compounds.

45. The lubricating oil composition of claim 34 wherein said dual additive composition is present in an amount comprising between about 0.005 and 0.7 wt. %
thereof.

46. The lubricating oil composition of claim 34 wherein said dual additive composition is present in an amount comprising between about 0.02 and 0.5 wt. %
thereof.

47. The lubricating oil composition of claim 34 wherein said first and second components are present in amounts such that the weight ratio of the amount of said second component to the amount of said first component is from about 1:0.3 to about 1:0.9

48. The lubricating oil composition of claim 47 wherein said first and second components are present in amounts such that the weight ratio of the amount of said second component to the amount of said first component is from about 1:0.4 to about 1:0.6

49. The lubricating oil composition of claim 40 wherein said third component is present in an amount of between about 0.6 and 2.8 wt. % thereof.

50. The lubricating oil composition of claim 37 wherein said second component is a polymer or interpolymer of an unsaturated mono-ester represented by the formula:

(III) wherein R2 is hydrogen or C1 to C5 alkyl and R4 is C1 to C20 alkyl, with the proviso that the average number of carbon atoms in the group constituting R4 in the polymer or interpolymer is from about 10 to about 18.

51. The lubricating oil composition of claim 37 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester and said second component is interpolymer of dialkyl fumarate and vinyl ester, wherein the alkyl portions of said dialkyl fumarate of said second component are derived from a mixture of alcohols.

52. The lubricating oil composition of claim 51 wherein the alkyl portions of said dialkyl fumarate of said second component interpolymer are derived from a mixture of alcohols having an average carbon number of from about 4 to about 20.

53. The lubricating oil composition of any one of claims 51 to 52 wherein said vinyl ester employed for both said first and second components is vinyl acetate.

54. The lubricating oil composition of claim 37 wherein said second component is interpolymer comprised of (a) esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons, and (b) at least one C6 to C46 alpha-olefin.

55. The lubricating oil composition of claim 54 wherein in said interpolymer of said second component, said esterified dicarboxylic acid or anhydride is derived from maleic anhydride.

56. The lubricating oil composition of claim 37 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester, and the mole ratio of said dialkyl fumarate and vinyl ester in the reaction mixture used to prepare said interpolymer is from about 1.3:1 to about 0.5:1.

57. The lubricating oil composition of any one of claims 54, 55 or 56 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl acetate.

58. The lubricating oil composition of claim 37 wherein said second component is interpolymer comprised of (a) esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons and (b) styrene.

59. The lubricating oil composition of claim 58 wherein said second component is a styrene esterified maleic anhydride interpolymer.

60. The lubricating oil composition of claim 58 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester and the mole ratio of said dialkyl fumarate and vinyl ester in the reaction mixture used to prepare said interpolymer is from about 1.3:1 to 0.5:1.

61. The lubricating oil composition of any one of claims 58, 59 or 60 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl acetate.

62. A lubricating oil concentrate comprising lubricating oil, and a dual additive composition in an amount effective to improve, relative to the absence of said dual additive composition, at least the low temperature flow properties of lubricating oil compositions derived from said concentrates, when containing viscosity index improver, said additive composition comprising as a first component, at least one low molecular weight polymer or interpolymer of unsaturated carboxy ester having the formula:

(I) wherein R' is selected from the group consisting of hydrogen and COOR, and wherein R is a C14 alkyl group, and as a second component at least one lubricating oil flow improver comprising low molecular weight non-ethylene-containing polymer or interpolymer containing pendent ester groups, and characterized by the presence within its structure of side chains of repeating methylene units derived from a mixture of alcohols.

63. The lubricating oil concentrate of claim 62 wherein said dual additive composition comprises from about 2 to about 90 wt. % of said lubricating oil concentrate.

64. The lubricating oil concentrate of claim 63, wherein said second component lubricating oil flow improver is at least one member selected from the group consisting of (a) polyacrylates, (b) poly-2-alkyl acrylates, and (c) interpolymers comprised of esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride and comonomer selected from the group consisting of vinyl ester, C6 to C46 alpha-olefin, and styrene.

65. The lubricating oil concentrate of Claim 64 wherein said first component is interpolymer of dicarboxy ester of Formula (I) wherein R' is COOR and vinyl ester represented by the formula:
(II) wherein R1 comprises an alkyl group containing from 1 to 18 carbon atoms.

66. The lubricating oil concentrate of claim 65 wherein said vinyl ester comprises vinyl acetate.

67. The lubricating oil concentrate of Claim 64 in combination with viscosity index improver comprising high molecular weight hydrocarbon polymer.

68. The lubricating oil concentrate of claim wherein said second component is a polymer or interpolymer of an unsaturated mono-ester represented by the formula:

(III) wherein R2 is hydrogen or C1 to C5 alkyl and R4 is C1 to C20 alkyl, with the proviso that the average number of carbon atoms in the group constituting R4 in the polymer or interpolymer is from about 10 to about 18

69. The lubricating oil concentrate of claim 65 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester and said second component is interpolymer of dialkyl fumarate and vinyl ester, wherein the alkyl portions of said dialkyl fumarate of said second component are derived from a mixture of alcohols.

70. The lubricating oil concentrate of claim 69 wherein the alkyl portions of said dialkyl fumarate of said second component interpolymer are derived from a mixture of alcohols having an average carbon number of from about 4 to about 20.

71. The lubricating oil concentrate of any one of claims 69 to 70 wherein said vinyl ester employed for both said first and second components is vinyl acetate.

72. The lubricating oil concentrate of claim 65 wherein said second component is interpolymer of (a) esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons, and (b) C6 to C46 alpha-olefin.

73. The lubricating oil concentrate of claim 65 wherein said second component is interpolymer of (a) esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride, wherein the carboxy groups are located on vicinyl carbons and (b) styrene.

74. The lubricating oil concentrate of claim 73 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl ester and the mole ratio of said dialkyl fumarate and vinyl ester in the reaction mixture used to prepare said interpolymer is from about 1.3:1 to 0.5:1.

75. The lubricating oil concentrate of any one of claims 73 or 74 wherein said first component is interpolymer of C14-dialkyl fumarate and vinyl acetate.

76. A method for improving at least the low temperature flow properties of a lubricating oil composition when containing a viscosity index improver, which comprises adding to said lubricating oil composition a dual additive composition comprising as a first component at least one low molecular weight polymer or interpolymer of unsaturated carboxy ester having the formula:

(I) wherein R selected from the group consisting of hydrogen and COOR, and where R' is a C14 alkyl group, and as a second component at least one lubricating oil flow improver comprising low molecular weight non-ethylene-containing polymer or interpolymer containing pendent ester groups, and characterized by the presence within its structure of side chains of repeating methylene units derived from a mixture of alcohols.

77. The method of Claim 76 wherein said second component lubricating oil flow improver is selected from at least one member selected from the group consisting of (a) polyacrylates, (b) poly-2-alkyl acrylates, and (c) interpolymers comprised of esterified C4 to C10 mono-ethylenically unsaturated dicarboxylic acid or anhydride and comonomer selected from the group consisting of vinyl ester, C4 to C46 alpha-monoolefin, and styrene.

78. The method of Claim 77 including incorporating said dual additive composition into a lubricating oil composition containing a viscosity index improver comprising high molecular weight hydrocarbon polymer.

79. The method of Claim 78 wherein said viscosity index improver has a number average molecular weight of between about 40,000 and 300,000.

80. The method of claim 76 wherein said first component is interpolymer of dicarboxy ester of Formula (I) wherein R' is COOR and vinyl ester represented by the formula:

(II) wherein R1 comprises-an alkyl group containing from 1 to 18 carbon atoms.

81. The method of claim 80 wherein said vinyl ester comprises vinyl acetate.

82. The method of claim 76 wherein said dual additive composition is included in said lubricating oil composition in an amount comprising between about 0.005 and 0.7 wt. % thereof.

83. The method of claim 76 wherein said dual additive composition is included in said lubricating oil composition in an amount comprising between about 0.02 and 0.5 wt. % thereof.

84. The method of claim 76 wherein said first and second components are present in amounts such that the weight ratio of the amount of said second component to the amount of said first component is from about 1:0.3 to about 1:0.9.

85. The method of claim 84 wherein said first and second components are present in amounts such that the weight ratio of the amount of said second component to the amount of said first component is from about 1:0.4 to about 1:0.6.