Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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- ~077194
1 This invention relates to lubricating oil composi-
2 tions comprising a major proportion of a lubricating oil and
3 a minor proportion of one or more oil-soluble polymers.
4 More particularly, the invention is concerned with one or
more polymeric additives which possess pour point depres-
6 sant and/or sludge dispersant and viscosity inde~ improving
7 properties when admixed with lubricating oil, unique compati-
8 bility, and have good oxidative and thermal stability.
9 The several useful classes of oil-soluble polymer
additives are:
11 A. copolymers of ethylene and a C8 to Clg
12 straight or branched chain alpha-olefin, or
13 terpolymers of ethylene, a C3 to Clg alpha-
14 olefin and a Cs to C28 non-con~ugated di-
olefin, or mixtures thereof;
16 B. "polyaminox" derivatives of oxidized co-
17 polymers of ethylene and a C3 to C18
18 straight or branched chain alpha-olefin,
19 or copolymers of ethylene, a C3 to C18
alpha-olefin and one or re Cs to C2g
` 21 diolefins, i.e. the reaction product
22 resulting from aminating said oxidized
23 copolymer with an amine of 2 to 60 car-
24 bon atoms and 1 to 12 nitrogen atoms;
C. fully esterified alkyl derivatives of co-
26 polymers of maleic anhydride and a l-olefin
27 having from 8 to 24 carbon atoms; and
28 D. alkyl ester-amide derivatives of copolymers
29 of maleic anhydride and a l-olefin having
from 8 to 24 carbon atoms.
31 A variety of compositions comprising high-molecu~
32 weight ethylene copolymers, including ~hose which incorp~te
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~)77~94
1 nitrogen, have been described previously as viscosity index
2 (hereafter designated V.I.) improvers for lubricants.
3 U.S. Patents 3,551,336, 3,697,429 and 3,790,480
4 disclose V.I. utility for copolymers of ethylene and one or
S more C3 to Clg c~olefins; and copolymers of ethylene, one
6 or more C3 to Clgc~-olefins~ and one or more Cs to C28 non-
7 con~ugated diolefins.
8 Oxidation of ethylene copolymers is well known,
9 e.g. U.S. Patent 3,756,924, as is the reaction of oxidized
ethylene copolymers with amines, e.g. U.S. Patent 3,785,980.
11 These amine reaction products of the oxidized polymers are
12 identified herein as "polyaminox" products.
13 U.S. Patent 3,316,177 teaches the reaction of poly-
14 amine with the reaction product of maleic anhydride and an
oxidized interpolymer of ethylene and propylene and their
16 use as sludge dispersants in lubricant and fuel compositions.
17 U.S. Patent 3,687,905 describes the preparation of
18 additives for fuels and lubricants by the reaction of an un-
19 saturated acid with an oxidized, degraded interpolymer of
ethylene and propylene, followed by reaction with a poly-
21 amine.
22 U.S. Patent 3,115,483 describes the preparation of
23 additives for ~et combustion fuels by the reaction of a 1:1
24 molar copolymer of an o~-olefin and maleic acid anhydride
with an aliphatic alcohol to produce a mixed mono- and di-
26 ester product which was thereafter reacted with a polyamine
27 and salicylaldehyde to produce a Schiff base derivative.
28 U.S. Patent 2,615,845 describes the preparation of
29 high molecular weight copolymers by the reaction of equi-
molar proportions of maleic anhydride and straight chainC~-
31 olefin having up to 20 carbon atoms and thereafter esterify-
32 ing the product with a mixture of saturated straight chain
~ 3
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1077194
1 alcohols ranging from 10 to 18 carbon atoms.
2 U.S. 2,543,964 describes lubricating oils improved
3 with respect to the pour point by the addition of copolymers
4 of olefins and esters of unsaturated polybasic acids.
Unfortunately many of these ethylene copolymers
6 and terpolymers useful as V.I. improvers do not exhibit use-
7 ful compatibility with many known pour point depressants
8 and/or dispersants so that they can be formulated together
9 as an additive package.
S~ch a unique compatibility has been found to
11 exist by the aforesaid ethylene polymers and an oil-soluble
12 pour point depressant and/or dispersant class of additive
13 materials comprising the reaction product obtained by (1)
14 esterifying a copolymer of a l-olefin, having between about
8 carbon atoms and about 24 carbon atoms per molecule, and
16 maleic acid anhydride with between about 1.2 moles and about
17 1.9 moles per mole of said anhydride of an aliphatic alcohol
18 containing between about 8 and about 18 carbon atoms per
19 lecule to produce a mixed mono- and diester product; (2)
reacting said ester product with between about 0.10 mole and
21 about 0.80 m~le of an amine of 2 to 60 carbon atoms and 1 to
22 12 nitrogen atoms.
23 This additive class is uniquely compatible in
24 mineral lubricating oils as an additive package with ethyl-
ene copolymers comprising ethylene and a higher C3 to C18
26 alpha olefin. Such ethylene copolymer comprises about 30 to
27 80 wt. ~/O ethylene, about 70 to 20 wt. % of a C3 to Clg alpha
28 olefin and about 0 to 15 wt. % of a Cs to C12 noncon~ugated
29 diolefin, having a number average molecular weight (Rn) in
the range of 40,000 to 500,000 with a ratio of the weight
31 average molecular weight (Mw) to the number average lecu-
32 lar weight (~w rn) of less than 10, and a crystalline content
:
`
,
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1077194
1 of less than 25 percent by weight. The compatibility and
2 utility extends as well to the "polyaminox" derivatives of
3 said ethylene copolymers and mixtures thereof.
4 Further it has been discovered that compatibility
is attained in an additive package comprising a ma3Or pro-
6 portion of mineral lubricating oil and a minor proportion
7 of a viscosity index improving and a pour point depressing
8 oil-soluble polymer mixture comprising a first copolymer of
9 from about 30 to about 80 wt. ~/O of ethylene, about 70 to
about 20 wt. ~b of a C3-Clg alpha olefin and about 0 to 15
11 wt. ~b of a Cs~C12 non-con~ugated diolefin; and, the alkyl
12 ester of a relatively low molecular weight copolymer of
13 maleic anhydride and a l-olefin having from 8 to 24 carbon
14 atoms, said alkyl substituents being a mixture of saturated
straight chain alcohols ranging from 6 to 18 carbon atoms.
16 Also, it has been discovered that the polymeric
17 compatibility is attained in an additive package comprising
18 a ma~or proportion of a mineral lubricating oil and a minor
19 proportion of a viscosity index improving and a pour point
depressing oil-soluble polymer mixture comprising (A) an
21 aminated oxidized ethylene copolymer obtained by oxidizing
22 a lubricating oil solution of a copolymer comprising ethyl-
23 ene and a higher C3 to Clg alpha olefin, at a temperature of
24 80C. to 300-C. to contain 0.01 to 10.0 wt. % oxygen, based
on the weight of said oil solution, and then aminating said
26 oxidized oil solution with an amine of 2 to 60 carbon atoms,
27 and 1 to 12 nitrogen atoms; and (B) the alkyl ester of a
28 relatively low lecular weight copolymer of maleic anhyd~de
29 and a l-olefin having from 8 to 24 carbon atoms, said alkyl
substituents being from a mixture of saturated straight
31 chain alcohols ranging from 6 to 18 carbon atoms.
32 An additive package for the puxposes of this
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~077194
1 disclosure is defined as mineral oil containing up to about
2 10 wt. % of the ethylene copolymer or its "polyaminox" deri-
3 vative and up to about 3 wt. % of said alkyl or alkyl-amide
4 derivatives of copolymers of maleic anhydride and a l-olefin
having from 8 to 24 carbon atoms.
6 Copolymers of ethylene and one or more C3 to C18
7 ~ olefins, and if deslred one or more Cs to C28 diolefins,
8 which may be utilized as the V.I. additive or to prepare the
9 polyaminox derivative, may comprise from 30 to 80 mole per-
cent of ethylene; 20 to 70 mole percent of a single C3 to
11 Clg straight or branched chain ~ ~olefin such as propylene,12 l-butene, l-pentene, l-hexene, 5-methyll-pentene, etc., or
13 mixtures thereof; and about 0 to 10 mole percent of one or
14 more Cs to C28 diolefins containing either one or two poly-
merizable bonds such as 1,4-hexadiene; 5methyl-2-norbornene;
16 2,4-dimethyl-2,7-octadiene; 1,5~hexadiene; 1,17-octadecadi-
17 ene; 5-(5'~hexenyl)-2~norbornene, etc. C3 to C8 ~ olefins
18 are preferred, and propylene is most preferred.
19 Also suitable, are mixtures of copolymers of
ethylene with individual ~ ~olefins in the C3 to Clg range,
21 mixtures of copolymers having the same or different
22 olefins and diolefins but differing in monomer content.
23 Particularly suitable, for a V.I. effect are co-
24 polymers having a high ethylene content, for example 60 to
80 wt. %, preferably 65 to 75 wt. % ethylene, and which may
26 be 3 to ~5 wt. % e.g., 5 to 10 wt. % crystalline, as general-
27 ly they give a greater V.I. effect. These high ethylene
28 polymers can be used per se, or frequently can be blended to
29 advantage with low ethylene conten~ (e.g., 35 to 50 wt. %
ethylene) polymer which in itself gives a good V.I. effect.
31 These high ethylene polymers and said blends are described
32 in U.S. Patents 3,551,336, 3,697,429 and 3,790,480.
~ 6
1(~77194
1 For some applications, particularly when the poly-
2 mer is to be the precursor of the "polyaminox" derivative,
3 the copolymers, especially those with at least 3 or 4 wt. %
4 diene are preferred, as the unsaturation in the diene, out-
side the backbone of the polymar, is believed to preferen-
6 tially oxidize, thereby providing many points for subsequent
7 amination without undue chain breakage and loss of molecular
8 weight and th~ckening efficiency.
9 The catalyst compositions for the preparation of
copolymers and terpolymers3 will generally comprise a prin-
11 cipal catalyst consisting of a transition metal compound
12 from Groups IVb, Vb and VIb of the Periodic Table of the
13 Elements, particularly compounds of titanium and vanadium,
14 and organometallic reducing compounds from Groups IIa, IIb
and IIIa, particularly organoaluminum compounds, which are
16 designated as cocatalysts.
17 Preferred principal catalysts of vanadium are
18 exempli~ied by: VOC13; VOC12 (OBu); VO(AcAc)2; VOC12(AcAc);
19 and V(AcAc)3, whe~e Bu is a n~butyl or isobutyl alXyl radi-
cal and (AcAc) is an acetylacetonate.
21 Preferred cocatalysts are exemplified by: Al(Et~;
22 Et2AlCl; EtAlC12; Et3A12C13; and Al(isoBu)3.
23 Representative examples of non-con~ugated dienes
24 useful as monomers for the preparation of suitable terpoly-
mers include in addition to those earlier set forth: 1,4
26 pentadiene; 1,5~heptadiene; 1,6~heptadiene; 1,6-octadiene;
27 5-methyl-1,4~hexadiene; 3,7~dimRthyl~1, 6~octadiene; 1,4-
28 cyclohexadiene; 1,5~cycloQoctadiene; 4~vinylcyclohexene; 4-
29 methylene cyclohexene; 4~ethylidene cyclohexene; 1-allyl-4-
isopropylidene cyclohexane, 3-allyL-cyclopentene; 4-allyl-
31 cyclopentene; l~isopropenyl-4 (4-butenyl) cyclohexane, 4,4'-
32 dicyclopentenyl; 4,4'~dicyclohexenyl; tetrahydroindene;
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iO7~1~4
1 methyltetrahydroindene; dicyclopentadiene; bicyclo (2,2,1)
2 hepta-2,5-diene; 5-methylene-2-norbornëne; 5-ethylidene-2-
3 norbornene; 5-methylene-6-methyl-2-norbornene; 5-methylene-
4 6,6-dimethyl-2~norbornene; 5-propenyl-2-norbornene; 5-iso-
propylidene~2-norbornene; 5-(3-cyclopentenyl)-2-norbornene;
6 and 5-cyclohexylidene-2-norbornene; 2,5-norbornadiene; etc.
7 These non-con~ugated dienes having a single poly-
8 merizable bond preferably contain 6 to 12 carbon atoms and
9 can be used in an amount of up to about 10 mole percent.
For those applications in which the copolymer as taught in
11 U.S. Patent 3,790,480 are desired, from about 0.1 to 2
12 weight percent of one or more diolefins containing prefer-
13 ably 5 to 18 carbon atoms and two polymerizable double bonds
14 can be used for the copolymer.
While these copolymers and terpolymers are essen-
16 tially amorphous9 they may contain up to 25 percent by
17 weight of crystalline segments as determined by X-ray or
18 differential scanning calorimetry.
19 Synthesis of the copolymers and terpolymers may be
conducted in a slurry process utilizing non~solvents such
21 as methyl chloride or methylene chloride, or in a solution
22 process utilizing moisture and catalyst poison free solvents
23 such as hexane, heptane, and toluene, in batch, staged or
24 continuous reactorsO Polymer made in a solution process is
preferred for the "polyaminox" preparation, since the poly-
26 mer cement, either before or after deashing, may be mixed
27 or fluxed with the oil to form a solution.
28 Solvent, monomers, principal catalyst and cocata-
29 lyst are fed to the reactor, supplied with means for with-
drawal of the heat of reaction, and maintained under con-
31 trolled agitation for a time, temperature, concentrations
32 and pressure sufficient to complete the reaction or ensure
~ 8 -
.
107719~
1 a steady~state equilibrium.
2 Suitable times of reaction will generally be in
3 the range of from about 1 to 300 minutes, temperature will
4 usually be in the range of 0C. to lOO~C. and pressures
fsom atmospheric to 160 psig may be employed. Monomers fed
6 to the reactor per 100 parts by weight of solvent may be in
7 the range of: ethylene, 2 to 20 parts by weight; C3 to Clg
8 ~ -olefin, 4 to 20 parts by weight; and when used to pre-
9 pare a terpolymer, non-con~ugated diolefin, 0.1 to 10 parts
by weight.
11 Principal catalyst, VOC13 for example, prediluted
12 with solvent, can be fed to the reactor so as to provide a
13 concentration in the range of 0.1 to 5.0 millimoles per
14 liter. Cocatalyst, for example Et3A12C13, also prediluted
if desired, can be fed to the reactor at the same time in an
16 amount equal to from about 2.0 to 20 les of cocatalyst per
17 mole of principal catalyst.
18 Suitable copolymers have number average molecular
19 weights (Mn) in the range of about 500 to 500,000. In
general, polymers having a narrow range of molecular weight,
21 as determined by the ratio of weight average molecular
22 weight ~M-w) to (Rn) are preferred. Polymers having a Mw rn
23 of less than 10, preferably less than 7, and most prefer-
24 ably 4 or less, are most desirable. Polymers in this range
may be obtained by selection of synthesis conditions and
26 addition of hydrogen in the range of 10 to 10,000 ppm of the
27 ethylene feed, and by post synthesis treatment such as ex-
28 trusion at elevated temperatures and under high shear
29 through small orifices, or by fractional precipitation from
solution.
31 The properties of a number of useful random poly-
32 mers and random terpolymers are summarized in Table I, which
33 follows:
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1~)77194
1 The above-described ethylene copolymers can be
2 oxidized and thereafter reacted with amines to produce the
3 "polyaminox" derivatives.
4 Oxidation of ethylene copoly~ers and reactions
with nitrogen containing compounds are both well known.
6 Oxidation pr~or to reaction can be carried out by numerous
7 processes including mechanical degradation, heating in air
8 or hydroperoxidation.
9 Particularly useful are ethylene copolymers oxi-
dized in mineral oil and subsequently reacted with amines.
11 In this process a wide variety of oils may be used for the
12 oxidation. The oils may range in viscosity from about 5 to
13 1000 SUS @100F., most preferably 80 to 200 SUS @100F.
14 They may be straight-run distillates in the lubricant range,
e.g., bolling above 600F., or further refined. Also suit-
16 able are synthetic hydrocarbon oils in the lubricant range
17 made by polymerization, oligomerization, alkylation of aro-
18 matics with olefins, and the like. Preferred, because they
19 give less undesirable by-products during oxidation, e.g.,
color bodies, are oils having a sulfur content of less than
21 0.25 weight percent, a nitrogen content of less than 25
22 micrograms per ml., and an aromatic content of less than 30
23 weight percent.
24 Oxidation of the copolymers and terpolymers dis-
solved in the oil is conveniently carried out, either in
26 batches or continuously, in a stirred reactor with air, or
27 air prediluted with an inert gas such as nitrogen or carbon
28 dioxide so as to minimize explosion hazards. The air, or
29 diluted air, may be introduced into the oil-polymer solution
in a finely divided state at a temperature in the range of
31 about 80C. to 300C., preferably 100C. to 230C. with
32 rapid agitation of the reactor contents.
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:
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1077~ 94
1 In general, in the range of 0.5 to 90, e.g., 4 to
2 60 weigh~ percent of the oil-polymer solution will be poly-
3 mer. Usually, about 20 to 60 weight percent of the solution
4 will be polymer when the polymer is o~ low mol. wt., e.g.,
with a number average molecular weight (Mn) less than
6 20,000. For polymers with Mn equal to or greater than
7 20,000, the preferred concentrations are in the rànge of 4
8 to 20 weight percent polymer, based on the total weight of
9 the oil-polymer solution.
Oxidation of the oil-polymer solution is conducted
11 for a time sufficient to i~part to the solution a combined
12 oxygen content of about 0.01 to 10.0, e~g., 0.1 to 8, pre-
13 ferably 0.1 to 5.0 weight percent, depending on the compo-
14 sition of the oil, the polymer and the concentration of
polymer in solution.
16 As used herein, such terms as "oxidized", or "oxi-
17 dized oil polymer solution" etc. indicates that alr or oxy-
18 gen containing gas is used for the oxidation, and precludes
19 the use of other oxidative reagents such as ozone.
Useful amine compounds for condensation with the
21 oxidized polymer-oil solutions to form the polyaminox prod-
22 ucts of this in~ention include amines of about 2 to 60, e.g.,
23 3. to 20, total carbon atoms and about 1 to 12, e.g., 1 to
24 6 nitrogen atoms in the molecule, which amines may be hydro-
carbyl amines or may include other groups, e.g., 1 to 4
26 hydroxy groups, alkoxy groups, amide groups, imidazoline
27 groups and the like.
28 Preferred amines are aliphatic, saturated amines,
29 and include those of the general formulae:
3l R-N-R" and R-N-(cH2)s-[-N-(cH2)s-]tN-R
32 R' R' R' R'
33 wherein R, R' and R" are independently selected from the
- 13 -
1C~77~94
1 group consisting of hydrogen; Cl to C12 straight or branched
2 chain alkyl radicals; Cl to C12 alkoxy substituted C2 to C6
3 alkylene radicals; C2 to C12 hydroxy or amino alkylene
4 radicals; and Cl to C12 alkylamino substituted C2 to C6
alkylene radicals; s is 2 to 6, preferably 2 to 4; and t is
6 0 to 10, preferably 2 to 6.
7 Examples of suitable amine compounds represented
8 by the above include: n~octyl amine; n-dodecyl amine; di-
9 (2-ethylhexyl) amine; 1,3-diaminoethane; 1,3-diaminopropane;
1,4-diaminobutane; 1,6-diaminohexane; diethylene triamine;
11 triethylene tetramine; tetraethylene pentamine; 1,2-propyl-
12 ene diamine; di-(1,2-propylene) triamine; di-(1,3-propylene)
13 triamine; N,N-dimethyl-1,3-diaminopropane; ~,N-di-(2-amino-
14 ethyl) ethylene diamine; N,N-di-(2-hydroxyethyl)-1,3-propyl-
ene diamine; 3-dodecyl oxy propylamine; Ndodecyl-1,3-pro-
16 pane diamine; diethanol amine; morpholine; tris-hydroxy-
17 methyl aminomethane (THAM); diisopropanol amine; etc.
18 Still other useful amine compounds include: ali-
19 cyclic diamines such as 1,4~di-(aminomethyl) cyclohexane and
heterocyclic nitrogen compounds such as imidazolines and N-
21 aminoalkyl piperazines such as 2~pentadecyl imidazoline; N-
22 (2-aminoethyl) piperazine; N~(3~aminopropyl) piperazine;
23 and N,N'-di(2-aminoethyl) piperazine.
24 Other alkylene amino compounds that can be used
include dialkylamino alkyl amines, such as dimethylamino
26 ethyl amine, dimethylamino propyl amine, methylpropylamino
27 amyl amine, etc.
28 Comm~rcial mixtures of amine compounds may advan-
29 tageously be used for the preparation of the polyaminox com-
positions of this invention. For example, one process for
31 preparing alkylene amines involves the reaction of an alkyl-
32 ene dihalide (such as ethylene dichloride or propylene di-
14 ~
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1077194
1 chloride) with ammonia, which results in a complex mixture
2 of alkylene amines wherein pairs of nitxogens are ~oined by
3 alkylene groups, forming such compounds as diethylene tri-
4 amine, triethylene tetramine, tetraethylene pentamine and
isomeric piperazines. Low cost poly(ethylene amines) com-
6 pounds having a composition approximating tetraethylene
rna. ~s
7 pentamine are available commercially under the trade namcs
8 Polyamine H, Polyamine 400 (PA-400) and Polyamine 500 (PA-
9 500). Similar materials may be made by the polymerization
of aziridine, 2-methylaziridine and azetidine.
11 The more important alkylene polyamine or aliphatic
12 polyamine compound, used in this invention, can be broadly
13 characterized as an alkylene amino compound containing from
14 2 to 12 nitrogen atoms wherein pairs of nitrogen atoms are
~oined by alkylene groups of from 2 to 4 carbon atoms.
16 Reaction of the æmine compound with the aforesaid
17 preferred oxidized polymer-oil solution takes place readily
18 at a temperature in the range of about 40C. to 300C.,
19 preferably at a temperature in the range of 100C. to 200C.
Accordingly, after the oxidation of the oil-polymer solution
21 has reached the desired level, the required amount of amine
22 compound, usually in the range of about 0.1 to 4.0 wt. %
23 based on the weight of the polymer, may be added with mixing
24 and the reaction mixture maintained at the required tempera-
ture while removing any water that forms. The time for com- -
26 pletion of the reaction of the amine compound with the oxi-
27 dized oil-polymer solution is in the order of about 15 min-
28 utes to ten hours depending on temperature, degree of mix~
29 ing and reactivity of the amine rompound. The final amina-
ted product will usually contain in the range of about 0.03
31 to 5, e.g. 0.1 to 3.0 wt. % nitrogen, based on the total
32 weight of the aminated polymer~in~oil solution.
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:
~077~94
1 The copolymers of maleic anhydride and l-olefin
2 which are useful for this invention, have number average
3 molecular welghts in the range of 1000 to 30,000. These co-
4 polymers are readily polymerized by conventional techniques
such as by a free radical polymerization promoter. The
6 alkyl ester is produced by esterification with an alcohol
7 after polymerization.
8 The copolymers of maleic anhydride and l-olefin
9 used for preparation of the esters and ester-amides were
earlier stated to be useful when having a Mn in the range of
11 1,000 to 30,000. Such a Rn range also substantially covers
12 the useful range of the ester and ester-amide derivatives.
13 The preferred ester and ester~amide derivatives have a Mn
14 ranging 1500 to 20,000 and optimally, the Rn ranges from
about 2,000 to 15,000.
16 Instead of maleic anhydride, one may also use
17 other ethylenically unsaturated dicarboxylic acid anhydrides
18 including itaconic anhydride and derivatives of maleic an-
19 hydride. Maleic anhydride is preferred, however.
Maleic anhydride derivatives for the purpose of
21 this disclosure include those of the generic formula:
22 Rl R2
23
24 C - C
26 0 ~ C C = 0
27 \ X /
28 wherein Rl and R2 are hydrogen or a halogen and X is oxygen,
29 NH, or NR3, wherein R3 is an alkyl group, preferably a Cl to
C40 alkyl. Suitable examples of such derivatives include
31 itaconic anhydride, N-ethyl maleimide, N-hexyl maleimide,
32 N-dodecyl maleimide, N~tetradecyl maleimide, ~-eicosyl male-
33 imide, N-tetracosyl maleimide, chloromaleic anhydride and
34 dichloro maleic anhydrideO
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1~7 719 4
1 The maleic anhydride is reacted with an aliphatic
2 l-olefin containing from 8 to 24 carbon atoms per molecule,
3 i.e. octene-l, nonene-l, decene-l, etc. through tetracosene-
4 1. All are "straight chain" l olefins; but also useful are
branched l-olefins as for example 2-methyl heptene-l; 2-
6 methyl hexadecene-l, and 2,~,4-trimethyl pentene-l. Mix-
7 tures of these l-olefins are suitable.
8 The reaction between the maleic anhydride and 1-
9 olefin, usually in about equal molar proportions, can con~
veniently be carried ou~ by mixing the l~olefin and maleic
11 anhydride in about equimolar amounts, and heating the mix-
12 ture ~o a temperature of 120 to 300Fo ~ preferably from
13 175 to 250F. A free radical polymerization promoter such
14 as azo-isobutyl nitrile, benzoyl peroxide, tobutyl perbenzo-
ate or di-t-butyl peroxide is normally used. Polymerization
16 time is normally 3 to 8 hours. The addition product thus
17 prepared is reacted with about 2.0 moles of an alcohol or
18 mixture of alcohols, per mole of maleic anhydride. Such
19 alcohols are straight chained or contain one methyl or ethyl
branch on the second carbon, and are ~aturated aliphatics
21 having from 6 to 18 carbon stoms~ The low lecular weight
22 polymer may be isolated by precipitation in methanol or iso-
23 propanol, filtering and vacuum drying in an oven. Further
24 details are set forth in U.S. Patent 3,706,704.
Preferred are those alcohols having from 10 to 18
26 carbon atoms which thus include decanol, dodecanol, tetra-
27 decanol, hexadecanol, octadecanol, 2-methyl-1-dodecanol,
28 etc.
: 29 The alkyl ester~amide derivatives are additives
which are highly useful as pour point depressants and¦or
31 dispersants, alone as well as in combination with the pre-
32 viously mentioned ethylene copolymers and terpolymers and/or
:
- 17
~077~94
1 the "pol~aminox" products.
2 The alkyl ester amide derivatives are prepared in
3 accordance with the pr~cedures used to prepare the alkyl
4 esters except that the precursor copolymer of maleic anhy-
dride snd l-olefin is not fully esterified. Rather the
6 molar amount of the alcohol is limited to from 1.2 mole to
7 1.9 mole of alcohol per mole of maleic anhydride. The alkyl
8 ester is thereafter reacted with sufficient amine to amin-
9 ate the balance of ~he carboxyl groups of the copolymer;
i.e. from 0.1 to 0.8 mole of amine is reacted with the re-
11 maining acidic part of the copolymer.
12 In general, useful amines include amines of about
13 2 to 60 e.g. 3 to 20, total carbon atoms and about 1 to 12,
14 e.g. l to 6 nitrogens, which amines may be hydrocarbyl
amines or may include other groups, e.g. hydroxy groups,
16 amide groups, imidazoline groups, etc. These useful amines
17 have been earlier set forth as useful for the amination of
18 the oxidized ethylene copolymers and terpolymers. Thus the
19 useful amines can be simple amines such as dodecylamine, di-
(2-ethylhexyl) amine, and ethylene diamine; and polyamines
21 including ethylenediamine, hydrazine, diethylenetriamine,
22 tetraethylenepentamine, di(methylethylene) triamine, N-(2-
23 hydroxy-ethyl) 1,2-ethanediamine, n-phenyl-ethylene diamine,
24 N-cyclohexyl-N'(2-amino ethyl)-1,2-ethane-diamine, pipera-
zines, etc.
26 The ethylene copolymers and terpolymers and their
27 polyaminox derivatives can be dissolved in oil for ease in
28 dispensing. This forms a concentrate which contains from 5
29 to 25 wt. % polymer with about 7 wt. % being preferred.
The ester or ester/amide polymers are dissolved in
31 oil in an amount of from 20 to 60 wt. % with about S0 wt. %
32 being preferred, to provide the concentrate.
~077194
1 These concentrates are mixed together to provide
2 the additive package of the invention~ In general, 90 to
3 98 parts by weight of the concentrate of the ethylene co-
4 polymer or its "polyaminox" derivative is blended with 10
to 2 parts by weight of the concentrate of the ester or
6 the amide/ester at 130F. for 1 hour. In the preferred
7 ratios mentioned above, this provides a concentrate in
8 which the V.I. improver and alkyl ester (includes ester-
9 amide) are present in ranges of about 6.3 to 6.9 wt. ~/O and
1 to 5 wt. %, respectively. The weight percents as used
11 herein are based on the total weight of the lubricant,
12 package, concentrate, etc. unless otherwise noted.
13 The diluent oils which can be used in these con-
14 centrates include those mineral oils utilized as solvents
for the polymer-oil solutions to be oxidized prior to
16 amination in preparation of the "polyaminox" derivatives.
17 Also suitable are lubricating oils derived from shale oil,
18 coal and tar sand and mixtures of the foregoing.
19 The additive packages can be incorporated in lub-
ricating oil compositions, e.g., automotive crankcase lu~ri-
21 cating oils, automatic transmission fluid (ATF) compositions,
22 etc., in concentrations within the range of about 7 to 20
23 wt. % of the total composition. Thus in said lubricating
24 oil compositions the V.I. improvers are preferably pxesent
in an a unt ranging from about 0.4 to 1.4 wt. % and the
26 dispersant esters (includes ester-amide) are present in an
27 amount ranging from about 0.07 to 1.0 wt. %. Lubricating
28 oils of said lubricating oil compositions include not only
29 mineral oils but also synthetic oils such as alkyl esters
of dibasic ac~ds, complex esters comprising dibasic acids,
31 polyglycols and alcohols~ polyglycols and carboxylic acid
32 esters of polyglycols~
~ 19 - ~
~077~94
1 The following tests were used to evaluate compati-
2 bility and utility of these additives.
3 Compatibility Test
4 Two additive concentrates are mixed together with
heating, e.g. up to about 150F., and agitation until ap-
6 psrently homogeneous upon visual examination. The test mix-
7 ture is stored at room temperature and at elevated tempera-
8 tures and periodically observed to detect precipitation,
9 flocculation or phase separation. If none of these occur
within the test period the mixture is considered compa~ible.
11 A further test is to use this apparently compat~le
12 mixture to formulate and evaluate a multi-graded oil, e.g.
13 lOW-30.
14 Pour Point Test
The pour test for lubricating oils as set forth
16 by ASTM D-86 determines the lowest temperature at which the
17 oil will pour under conditions specified thereby.
18 Slud~e Inhibition Bench (SIB) Test
19 The dispersant activity of the additives was de-
termined in a SIB test as follows:
21 A used, dispersant-free, automotive mineral lubri-
22 cating oil containing a V.I. i~prover, a pour point depres-
23 sant, and a zinc dialkyldithiophosphate antiwear agent,
24 which oil had an original viscosity of 325 SUS at 100F.,
was obtained by pooling the oil drained from the crankcase
26 of a fleet of taxicabs operating in New York City. The
27 used oil was centrifuged in heavy-walled 50 ml. tubes at
28 about 16,000 RPM for one-half hour and the clear supernatant
29 oil, free of sludge but containing dissolved therein sludge
precursors, was decanted from the sludge and used in the 5IB
31 test.
32 In conducting the test 0.5 wt. Z of the additive
- 20
1C~77~94
1 was dissolved into the used, centrifuged oil and added to
2 preweighed centrifuge tubesO The tubes were stored in a
3 heating block at 280Fo for 16 hours, along with tubes con-
4 taining blanks, l.e., containing only the centrifuged used
oil to which no dispersant additive was added. After heat-
6 ing for 16 hours, the tubes were centri~uged at 16,000 RPM
7 for one-half hour and the supernatant oil decanted and dis-
8 carded. The tubes were inverted and allowed to drain in a
9 rack for not more than 15 minutes, after which the walls of
each tube were rinsed with 25 ml. of pentane, taking care
11 not to disturb the sludge compacted in the tip of each tube.
12 A second 25 ml. portion of pentane was added to each tube
13 and the sludge dispersed and any occluded oil dissolved by
14 gentle shaking. The tubes were then centrifuged in a refri-
gera~ed centrifuge at 16,000 RPM for one-half hour, the pen-
16 tane decanted and discarded. After rinsing the exterior of
17 each tube with acetone, the tubes and contents were allowed
18 to dry at room temperature for one hour and weighed, the
19 weight of sludge in each tube being obtained by difference.
The effectiveness of the dispersant is expressed as the
21 weight (in milligrams) of sludge in each tube as compared to
22 the weight of sludge found in the blanks, which had no
23 dispersant.
24 The oils were formulated with sufficient amounts
of additives so that the viscometric requirements of SAE
26 lOW-30 and lOW~40 were met.
27 EXAMPLE 1
28 A typical laboratory preparation of the alkyl
29 ester of maleic anhydride~l-olefin copolymer designated
Polymer C is as fol~ows:
31 To a 500 mlO 4-necked flask having a stirrer,
32 thermometer, and charging funnel were added; 80 grams of
21 ~
~077194
xylene, 24.5 grams (0.25 mole) of maleic anhydride and 76
2 grams ~0.30 moles) of a Clg olein mixture. The reactants
3 were heated to 145C. and 1.1 gram di-t-butyl peroxide was
4 added. The reaction mixture was cooled to ambient temE~era-
5 ture and then poured slowly into 2 liters of chilled isopro-
6 panol. The precipitated copolymer was filtered and dried in
7 a vacuum oven overnight at 30C. The copolymer yield was
8 88% of theoretical and upon analysis gave 75.13 wt. % car-
9 bon and 10.83 wt. % hydrogen. Its molecular weight Mn was
10 determined to be about 2800 by vapor phase osmometry.
11 To 35 grams (0.1 mole) of the isolated copolymer,
12 41.4 grams (0.2 mole) of C12~18 commercial alkanol, 30 ml.
13 of toluene and 0.5 grams of p-toluene sulfonic acid were
14 added. The mixture was heated to 130~150C. for 12 hours
15 to remove the water formed by esterification. A sample of
16 the reaction product was dialyzed for 3 hours with boiling
17 toluene in a Soxhlet extraction device, using a semi-
18 perme~ble rubber membrane to remove low molecular weight
19 components. The residue, representing esterified copolymer,
20 was obtained in 90 wt. ~/1, yield and had a number average
21 molecular weight of about 5000, a carbon content of 76.7 wt.
22 %, and a hydrogen content of 11.7 wt. %.
23 The Clg l-olefin used was about 93% total mono-
24 olefin and 7% paraffin; about 80% of this monoolefin was
25 the alpha type and about 14% was the vinylic type.
26 The commercial C12_1g al~anol that was used was a
27 mixture of synthetic alcohols, about 2 wt. % of Clo alcohol,
28 about 56 wt. % C12 alcohol, about 21 wt. % of C14 alcohol,
29 about 10 wt. % of Cl6 alcohol and about 11 wt. % of C18
30 alcohol.
31 EXA~D?LE 2
32 The prDcedure of Example 1 was used to prepare
- 22 -
1~7 71 9 ~
1 another alkyl ester of the maleic anhydride l~olefin copoly-
2 mer. The commercial C12O18 alkanol was replaced by a mix-
3 ture of C6~1g straight chain alcohols derived from fatty
4 acids and containing about 3 wt. % C6 alcohol, 10 wt. % C8
alcohol, 8 wt. % Clo alcohol, 45 wt. % C12 alcohol, 18 wt.
6 % Cl~ alcohol, 7 wt. % C16 alcohol and 10 wt. % Clg alcohol.
7 EXAMPLE 3
8 The following preparations exemplify the prepara-
9 tion of partial ester-partial amide derivatives of a co-
polymer of maleic anhydride and l-olefin. The procedure of
11 Example 1 was followed except that the C12~18 alcohol mix-
12 ture was reacted in an amount of 33 grams (1.6 mole/mole
13 anhydride) and the resulting product was not isolated but
14 thereafter aminated as follows:
To the above mixture at 280~F., 3.7 gms. (0.4
16 mole) of Polyamine 400 was added. The mixture was then
17 stripped with nitrogen for 2 hours while at 280F. The
18 final product, upon dialysis, has a number average molecular
19 weight of 13,400, a nitrogen content of 2.4 wt. %, a carbon
contentof 74.9 wt. %, and a hydrogen content of 10.8 wt. %.
21 EXAMPLE 4
22 The procedure of Example 3 was followed except
23 that the alcohol addition was increased to 35 grams (1.7
24 mole/mole of maleic anhydride) and the Polyamine 400 addi-
tion was reduced to 207 grams (0.3 mole/mole of maleic anhy-
26 dride).
27 The final product, upon dialysis, has a number
28 average molecular weight of 10,200, a nitrogen content of
29 1.1 wt. %, a carbon content of 75.6 wt. % and a hydrogen
content of 11.8 wt~ %.
31 EXAMPLE 5
32 The procedure of Example 3 was followed except
- 23 -
.
-
~07ql94
1 that the alcohol addition was increased to 37 grams (1.8
2 mole/mole of maleic anhydride) and ~he Polyamine 400 addit~on
3 was decreased to 1.9 grams (0.2 mole/mole of maleic anhy-
4 dride).
The final product, upon dialysis, has an average
6 number molecular weight of 11,400, a nitrogen content of
7 1.8 weight %, carbon content of 75.0 wt. % and a hydrogen
8 content of 11.5 wt. %.
9 EXAMPLE 6
The procedure of Example 1 was followed except
11 that the octadecene (Clg alphaolefin mixture) was replaced
12 by 0.30 moles of octene-l.
13 EXAMPLE 7
14 The procedure of Example 1 was followed except
that the octadecene (Clg alpha-olefin mixture) was replaced
16 by 0.30 moles of 2,4,4~trimethyl pentene~lO
17 The products of Examples 1-7 were tested in Sol-
18 vent 150 Neutral, which is a neutral solvent-extracted
19 mineral lubricating oil having a viscosity of about 150 SUS
at 100F. and a pour point of 0F. and compared with two
21 commercially available additiYes and a control with the fol-
22 lowing results.
23 BLE II
24 Pour Test S 15QN _ SIB Test
V/~I our Po nt o
26 Additive Treat Blend. F. VtvAI* Treat M~. Slud~e
27 Prod.Ex. 1 0.1 -20 0.5 22
28 Prod.Ex. 2 0.1 -20 0.5
29 Prod.Ex. 3 0.1 -25 0.5 8
Prod.Ex. 4 0.1 -20 0.5 12
31 Prod.Ex. 5 0.1 -20 0.5 15
32 Prod.Ex. 6 0.1 -25 - 18
33 Prod.Ex. 7 0.1 -20
~.
- 24 -
i~77194
1 TABLE II (continued)
2 Comm.Lube oil
3 pour depressant 0.1 -20 - -
4 Comm.ashless dis-
5 persant - - 0.5 8
6 None - 0 - 25
7 * % AI is ~he weight percent active ingredient.
8 These data demonstrate that some of the polymers
9 (see Ex. 3, 4, S, and 6) are not only pour point depres-
10 sants but also dispersants. Also several of these polymers
11 (see Examples 1 and 2) are pour point depressants as would
12 be expected from the teachings of U.S. Patent 2,542,542;
13 however, this patent does not disclose Example 7.
14 EXAMPLE 8
Crankcase oils were formulated with base stocks
16 obtained from seven different refineries (base stocks A
17 through G). These base stocks have viscosities at 210F.
18 of about 5 to 5.5 cs, and natural pour points of about 0 to
19 +lSF. To these oils sufficient amounts of Polymer A' or
20 Polymer B' and Polymer Product of Example 1 or Polymer Pro-
21 duct of Example 3 were added so that they meet the kinematic
22 viscosity requirements for SAE Graded oils of lOW/30 or lOW/
23 40 and have pour points of 15F. or below; the characteris-
24 tics of these blends are shown in Table III.
2~ Polymer A' is a blend of equal amounts of ethyle
26 propylene copolymer (about 67 wt. % ethylene~ having a ~n
27 of about 40,0Q0 and an ethylene~propylene copolymer (about
28 46 wt. % ethylene~ having a Mn of about 559000; both of said
29 copolymers being prepared by a Ziegler-Natta synthesis in
30 the presence of hydrogen as a moderator.
31 Polymer B' is obtained by oxidation of a mixture
3~ of 4~/O by weight of said ethylene~propylene copolymer (about
33 67 wt. % ethylene), having a Mn of about 40,000, and 60% by
34 weight of said ethylene-propylene copolymer (about 46 wt. %
- 25 -
1~77~g4
1 ethylene), having a Mn of about 55,000, to a thickening ef-
2 ficiency of 1.4 and amidation of 13.6 wt. % of said oxidized
3 copolymer blend in mineral oil at 150C. for 5 hours with
4 diethylenetriamine to a nitrogen content of about 0.04 wt.
% after heavy nitrogen sparging to remove unreacted amine.
6 Substantially all of the amidation occurs on the oxidized
7 ethylene-propylene copolymers.
8 TABLE III
pour
10 SAE VI Polymer Pour Point,*
11 Basestocks Grade Improver Depressant F.
12 A lOW/40 Polymer A' Prod. Ex. 1 -15
13 B lOW/40 Polymer A' Prod. Ex. 1 -25
14 C lOW/40 Polymer A' Prod. Ex. 1 -35
D lOW/30 Polymer A' Prod. Ex. 1 -35
16 E lOW/40 Polymer A' Prod. Ex. 1 -20
17 F lOW/40 Polymer A' Prod. Ex. 1 -25
18 G lOW/40 Polymer A' Prod. Ex. 1 -20
19 G lOW/40 Polymer A' Prod. Ex. 3 -20
G lOW/40 Polymer B' Prod. Ex. 3 -20
21 *Determined by ASTM D-97
22 EXAMPLE 9
23 Compatibility of polymer blends useful as additive
24 packages of the invention, 1.~. blends of ethylene copoly-
mers and terpolymers (Polymers A') and "polyaminox" deriva-
26 tives (Polymers B') with the alkyl esters and amide-ester
27 derivatives of the copolymer of maleic anhydride and l-ole-
28 fin, are shown in the following Table IV:
29 TABLE IV
Wt. % Blend of Polymer Concentrates* Stora~e Stability Days
32 A' B' Prod.Ex.l Prod.Ex.3 75F. 150F. 180F.
33 94 - 6 - 300 - 25
34 96 - - 4 >50 ~ 14
- 26 -
-
~oms~
1 - 96 4 - > 50 > 14
2 - 96 - 4 ~50 > 14
3 *The concentrates for Polymers A' and B' were about 7 wt. %
4 and for the Polymer Products of Ex. 1 and 3 were about 50
wt. %, respectively.
6 After the storage stability tests, the above addi-
7 tive mixtures were found compatible.
:'
- 27 -
,; , .. .
. .
