Note: Descriptions are shown in the official language in which they were submitted.
1~1861
,_ .
HYDROCARBON COMPOSITIONS CONTAINING
POLYOLEF IN GRAFT POLYMERS
(D#78,317)
FIELD OF THE INVENTION
. This invention relates to hydrocarbons including
hydrocarbon lubricating oils. More particularly, it relates to
hydrocarbons which contain polymers which permit attainment of
improved properties.
BACXGROUND OF THE INVENTION
A~ is well known to tho~e skilled in the art,
hydrocarbon lubricating oils must be formulated, as by addition
of variou~ additives, to $mprove their properties.
In the ca~e of lubricating oils, typified by those
employed in railway, automotive, aircraft, 0arine etc. service,
~t ~ found that they become degraded during use due inter alia
to ~ormation of ~ludgo which may be g-nerated by deterioration
of the oll or by introduction of undesirable components from
other source~ including the fuel or the combu~tion air. In
ordor to maintain and improve the properties of the lubricating
oil, variou~ additives have heretofore been provided; and these
have been intonded to improve the viscosity index, dispersancy,
oxidativo stability, otc. It i~ an object of this invention to
provide an additivo ~y-tem which permit~ attainment of improved
hydrocarbon~. Other ob~ect~ will be apparent to those skilled
in the art.
'~'
18~1
,, .
288-2757
STATEMENT OF THE INVENTION
In accordance with certain of its aspects, this invention
is directed to a polymer comprising an oil-soluble, substantially
linear, carbon-carbon backbone polymer bearing units thereon derived
from a functional monomer containing at least one atom of nitrogen,
sulfur, or oxygen in a heterocyclic ring structure.
According to another aspect of the present invention there
is provided the process for preparing a product polymer having an
oil-soluble, substantially linear, carbon-carbon backbone polymer
bearing units thereon derived from a functional monomer which con-
tains at least one atom of nitrogen, sulfur, or oxygen in a hetero-
cyclic ring structure which comprises
lntimately admixing in a reaction mixture (i) an oil-
soluble, substantially linear, carbon-carbon backbone polymer, (ii)
functional monomer containing at least one atom of nitrogen, sulfur,
or oxygen in a heterocyclic ring structure and (iii) a free-radical
initiator;
maintaining the temperature of the reaction mixture at a
temperature at least as high as the decomposition temperature of
said initiator thereby effecting decomposition of said initiator
and bonding of said functional monomer to said backbone polymer and
forming a product polymer having an oil-soluble, substantially
linear, carbon-carbon backbone polymer bearing units thereon derived
from a functional monomer which contains at least one atom of nitro-
gen, sulfur, or oxygen in a heterocyclic ring structure; and
recovering said product polymer having an oil-soluble,
~A
~ - 2 -
-
- 2a - 288-2757
substantially linear, carbon-carbon backbone polymer bearing units
thereon derived from a functional monomer which contains at least
one atom of nitrogen, sulfur, or oxygen in a heterocyclic ring
structure.
DESCRIPTION OF THE INVENTION
The charge polymer which may be employed in practice of
the process of this invention may include an oil-soluble, substan-
tially linear, carbon-carbon backbone polymer. Typical carbon-
carbon backbone polymers, prepared from monomers bearing an ethyl-
enically unsaturated polymerizable double bond, which may be em-
ployed include homopolymers or copolymers prepared from monomer con-
taining the grouping C=C including C=C-R" C=C
A A
wherein
A may be a hydrogen, hydrocarbon such as alkyl, aryl (par-
ticularly phenyl) etc., -OOCR typified by acetate or less preferred
acyloxy (typified by -OOCR);
halide, etc. R" may be divalent hydrocarbon typified alkyl-
ene, alkarylene, cycloalkylene, arylene, etc.
Illustrative of such monomers may be acrylates, methacry-
lates, vinyl halides (such as vinyl chloride), styrene, olefins suchas propylene, butylene, etc.; vinyl acetate; dienes such as buta-
diene, isoprene, hexadiene, ethylidene norbornene, etc. Homopoly-
mers of olefins (such as polypropylene, polybutylene, etc.), dienes
~such as hydrogenated polyisoprene), or copolymers of ethylene, with
e.g. butylene and higher olefins, styrene, isoprene and/or butadiene
may be employed.
'Al 2a -
1~7186~
,
The preferred carbon-carbon backbone polymers include
those selected from the group consisting of ethylene-propylene
copolymers (EPM or EPR) and ethylene-propylene-diene third
monomer terpolymers ~EPDM or EPT).
When the charge polymer is an ethylene-propylene
copolymer (EPM), it may be formed by copolymerization of
ethylene and propylene under known conditions~ preferably
Ziegler-Natta reaction conditions. The preferred EPM
copolymers contain units derived from the ethylene in amount of
40-70 mole ~, preferably 50-60 mole %, say 55 mole %r the
remainder being derived from propylene.
The molecular weight Mn of the EPM copolymers which
lS may be employed may be 10,000-1,000,000, preferably
20,000-200,000 ~ay 140,000. The molecular weight distribution
may be character$zed by MW/Mn of les~ than about 15, preferably
1.2-10, ~ay 1.6.
Illu~trative EPM copolymer~ which may be employed in
practice of tho proce~ of thi~ invention may be those set
forth in the following table, the first listed being preferred:
r t ~ TABLE
A 25 A. The Epsyn brand of EPM marketed by Copolymer Rubber
and Chemical Corporation conta$ning 60 mole % of units derived
from ethylone and 40 mole % of units derived from propylene,
having a mol-cular w-ight Mn of 140,000 and a MW/Mn of 1.6.
B. The Epcar~505 brand of EPM marketed by B. F. Goodrich
Co., contalning 50 mole % of units derived from ethylone and 50
mol~ % of unit~ derived from propylene and having a Mn f
25,000 and a polydi~per~ity index of 2.5.
C. The Esprene~ brand of EPR marketed by Sumitomo
Chemical Co., containing 5S mole % of units derived from
ethylene and 45 mole ~ of units derived from propylene and
having a Mn of 25,000 and polydisper~ity index of 2.5t
;~ra~e mq,rk
-3-
. .
~ 2 ~1 ~61
When the charge polymer is a terpolymer of
ethylene-propylene-diene third monomer ~EPT or EPDM), it may be
formed by copolymerization of ethylene, propylene, and diene
third monomer. The third monomer is commonly a non-conjugated
diene typified by dicyclopentadiene; 1,4-hexadiene: or
ethylidene norbornene. Polymerization is effected under known
conditions generally comparable to those employed in preparing
the EPM products. The preferred terpolymers contain units
derived from ethylene in amount of 40-70 mole %, preferably
50-65 mole %, ~ay 60 mole ~ and units derived from propylene
in amount of 20-60 mole %, preferably 30-50 mole %, say 38 mole
% and units derived from diene third monomer in amount of
0.5-15 mole %, preferably 1-10 mole %, say 2 mole ~. The
molecul~r weight M~ of the terpolymers may typically be
10,000-1,000,000, preferably 20,000-200,000, say 120,000.
Molecular weight distribution of the useful polymers is
preferably narrow vlz a MW/fin of typically less than 15,
preferably 1.5-10, ~ay about 2.2.
Illu~trative EPT terpolymer~ which may be employed in
practice of the proces~ of thi~ invention may be those set
forth in the following table, the first listed being preferred:
TAB~E
A. The Ep~yn 4006 brand of EPT marketed by Copolymer
~ubber and Chemical Corp., containing 58 mole % of units
derived from ethylene, 40 mole % of unit~ derived from
propylene, and 2 mole ~ of units derived from ethylidene
norbornene and having a MW/Mn of 2.2 and a molecular weight Mn
of 120,000.
B. The Ortholeum 5655 brand of EPT marketed by DuPont
containing 62 mole % of units derived fro~ ethylene, 36 mole S
of units derived from propylene, and 2 mole % of units derived
from 1,4-hexadiene and having a ~n f 75,000 and a
polydi~persity index MW/Mn of 2.
de rn~rk 4
~ ~ 7~
C. ~he Ortholeum 2052 brand of EP~ marketed by DuPont
con~aining 62 mole % of units derived from ethylene, 36 mole %
of units derived from propylene, and 2 mole ~ of units derived
from 1,4-hexadiene and having a Mn of 35~00~ and a
polydispersity index MW/Mn of 2.
D. The Royalene~brand of EPT marketed by Uniroyal
containing 60 mole % of units derived from ethylene, 37 mole %
of units derived from propylene, and 3 mole % of units derived
1~ from dicyclopentadiene and having a Mn of 100,000 and a
polydispersity index MW/Mn of 2.5.
E. The Epsyn 40A brand of EPT marketed by Copolymer
Rubber and Chemical Corp. containing 60 mole % of units derived
from ethylene, 37 mole ~ of units derived from propylene~ and 3
mole % of un$t~ der$ved from ethylidene norbornene and having a
Mn ~ 140,0oo and a polydispersity index MW/Mn of 2.
~ he EPM and EPT polymers may contain minor portions
ttypically le~a than about 30~) of other units derived from
other copolymerlzable monomers.
It i~ a feature of the process of this invention that
there may be bonded onto these oil-soluble, substantially
linear, carbon-carbon, backbone polymers, units derived from a
functional monomer wh$ch contains at least one of nitrogen,
suliur, or oxygen in a heterocyclic ring. When the functional
monomer include~ a polymerizable carbon-carbon ethylenically
un~aturated double bond, (as is the case for oxample with the
reaction prcduct of allyl glycidyl ether and phenothiazine)
bonding may be effected as by graft polymerization under graft
polymerizat$on condition~. In th$~ instance, the product may
be a graft polymer.
When the functional monomer does not contain a
polymerizable carbon-carbon ethylenically unsaturated double
bond (as is the case for example, with the preferred
e rna~fc
-5-
phenothiazine), then bonding may be effected in the presence of
a free-radical initiator catalyst.
It i8 believed that best anti-oxidant activity in
the desired polymer product is attained by bonding heterocyclic
compounds which exhibit anti-oxidant activity when present in
unbonded form. Preferred of these latter is phenothiazine.
The functional monomers which may be employed may be
monocyclic, or polycyclict and the nitrogen, sulfur or
oxygen may be contained in the same or a different ring. In
the preferred embodiment, the functional monomer may be
polycyclic and the nitrogen and sulfur may be in the same
heterocyclic ring.
The functional monomer can be heterocyclic/aromatic
or heterocyclic compound containing ~ulfur, nitrogen or oxygen,
or comblnation thereof. The compounds which may be used as the
functional monomer includ-s
1) phenothlazine ~nd ring or/and N-~ub~tituted
. phenothiasine. Sub~tituent~ may include hydrocarbon
radical~ selected from the group con~i~ting of alkyl,
alkenyl, cycloalkyl, aryl, alkaryl, or heterocyclic,
including ~uch radicals when containing oxygen,
nitrogen, ~ulfur, halide or combinations thereof.
$ypically, the ring-~ub~tituted phenothiazine may
include alkyl or alkenyl phenothlazine~, alkoxy
phenothiazlne~, hydroxy alkyl phenothiazines,
aminophenothiazine~, nitrophenothiazine~,
3-formyl-10-alkyl-phenothiaz~ne,
2-amiAo-4-(2-phenthiazinyl) thiazole, alpha
(2-phenothiazinyl) thioacetomorpholide, etc
Typi¢al N-~ubstituted phenothiazines may include
N-vinyl phenothiazine, N-acrylamidomethyl
phenothiazine, beta-(N-phenothiazinyl) ethyl vinyl
ether, beta-(N-phenothiazinyl) ethyl methacrylate,
reaction products of allyl glycidyl ether or glycidyl
methacrylate with phenothiazines etc.
1271861
2) imidazoles or benzimidazoles, such as
2-mercaptobenzimidazole, 2-mercapto toluimidazole or
2-mercapto-1-urethyl imidazole; etc.
3) thiazoles or benzothiazoles, such as
4-methyl-5-vinylthiazole, 2-amino-4-methylthiazole,
2-mercapto-4-phenylthiazole,
2-mercaptobenzothiazole; etc.
4) triazoles and benzotriazole~, such as
3-mercapto-lH-1,2,4-tr$azole,
3-Amino-S-methylthio-1~-1,2,4-triazole~ etc.
S) thiadlazolos, benzothiadiazoles, thiazolines and
benzothiazolines, thiazolidine. They may include
2-mercapto-thiazolinè, 1,2,5-thiadiazoline~ etc.
6) pyrlmldlne,including 2-amino-4-methylpyrimidine,
2-morcaptopyrimidine~ etc.
7) pyridine~, such as 2-mercapto pyridine, 4-mercapto-
pyridine, 2-mercaptopyridine-N-oxides etc.
8) piporidine~ and pyrroiidinonos~
9) ox~zole~ and benzoxazolos, such a~
2-morcaptobenzoxazole5 etc.
10~ merc~ptophenols, thiomorpholine, 6-mercapto-purine,
2-thiophenomethyl amino.
Preferred of the functional monomer~ is phenothiazine
which is a three-ring compound containing the nitrogen and
sulfur in the same ring. It i~ preferred to use one functional
monomer although it may be possible to use more than one
functional monomer, i.e., to bond them to the polymer either
~imult~n-ously or sequentially,
-7-
1 ~ 7~
In practice of the process of this invention, 100
parts of charge EPM or EPT may be added to 100-1000 parts, say
300 parts of diluent-solvent. Typical diluent-solvent may be a
hydrocarbon solvent such as n-hexane, n-heptane,
tetrahydrofuran, or mineral oil. Preferred solvent may be a
commercial hexane containing principally hexane isomers.
Reaction mixture may then be heated to reaction conditions of
60C-180C, preferably 150C-170C, say 155C at 15-300 psig,
preferably 180-220 psig, say 200 psig.
Functional monomer, typically phenothiazine, is
admitted in amount of 1-40 parts, say 2 parts, as a solution in
2 - 20 part~, ~ay 8 parts of diluent-solvent-typically tetra-
hytrofuran (THP). There is also added a solution in hydro-
carbon of free radical initiator. Typical free radical
initiator~ may include dicumyl peroxide, di-t-butyl peroxide,
benzoyl peroxide, di-isopropyl peroxide,
azobisi~obutyroni~rile, etc. The ~olvent is preferably the
~ame ~ that in which the EPM or EPT i9 dissolved. The
~nitiator may be atded in amount of 0.2-40 parts, ~ay 1 part in
0.8-120 part~, ~ay 3 parts of solvent hexane.
The reaction is carried out at a temperature at
least as high a~ the decomposition temperature of the
init$ator, typically 60C or higher.
,
IReaction i~ typically carried out at 60C-180C, say
155C and 180-220 psig, say 200 psig during which time bonding
of the functional monomer onto the ba~e EPM or EPT polymer
occur~. o~ ~-3 1~ 60
Typically the product may by contain 0.1 - 60,~say 3
units derived from functional monomer per 1000 carbon atoms of
the charge backbone polymer.
For ease of handling, the polymerization solvent may
be exchanged with a heavier solvent such as SUS lOO~oil
~ ~e ~ -8-
~ 7 . ~718~i~
~ typified by SN0-100~ Product polymer is typically obtained as
a solution of 4-20 parts, say 8.5 parts thereof in 80-96 parts,
say 91. 5 parts of solvent.
It is a feature of this invention that the
so-prepared polymer may find use in lubricating oils as
multifunctional additive (e.g. dispersant, viscasity index
$mprovers which provide anti-oxidant properties, etc) when
pre~ent in effective amount of 0.2-5 w~, preferably 0.4-3 w~,
Jay 0. 9 w%.
Lubricating oils in which the multifunctional
additives of this invention may find use may include
automotivo, aircraft, marine, railway, etc. oil~; oils used in
lS ~park lgnition or compre~ion ignitiont ~ummer or winter oils;
et¢. Typically the lubricating oil~ may be characterized by an
ibp of S70F-660P, ~ay 610Ft an ep of 750F-1200F, say
1020Pt and an API gravlty of 25-31, say 29.
A typical lubricating oil in which the polymer of
thi~ invention may be present may be a standard SAE 5~l-30
hydrocarbon motor oil formulation having the following
compositions
~ l-r~e ~
_g_
1;~71~
TABLE
W96
Base Oil 82
5 -Viscosity Index Improver 9
(10 w% ethylene-propylene copolymer
in 90~ inert oil)
-Standard Additive Package: 9
Polyisobutenyl (Mn 1290) succinimide
~dispersant);
calcium sulfonate (detergent);
Zinc dithiopho~phate ~anti-wear);
dl-nonyl diphenyl amine ~anti-oxidant);
4,4'-methylene-bis (2,6-di-t-butyl phenol)
lS (antioxidant);
Uoe of the additive of thiR invention makes it
pos~ible to readily lnorea~e the viscosity index by 25-40
units, say 35 units and to obtain improved ratings on the tests
mea~uring the disperJancy of the ~y~tem. The viscosity index
i~ determined by A8TM Te~t D-445.
Practice of the process of this invention will be apparent
to tho~e skilled in the art from the following examples
wher-in, as elsewhere in this specification, all parts are
part~ by weight unle~ otherwise ~et forth. Control examples
are d-~ignated by an ast-risk.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLE I
In thi~ example which de~cribos the best mode
presently known, the charge EPM polymer i~ the Epsyn brand of
polymer of molecular weight Mn f 140,000, of MW/Mn ratio of
1.6, and containing 60 mole % of units derived from ethylene
and 40 mole ~ of unit~ derived from propylene. 100 parts of
--10--
1~71~
\
this polymer are dissolved in 300 parts of commercial hexane
and added to a reaction vessel.
The reaction vessel is purged with nitrogen and
heated to 155C at 200 psig. Phenothiazine (2 parts) dissolved
in 8 parts of tetrahydrofuran is added followed by a solution
of 1 part of dicumyl peroxide initiator in 3 parts of
commercial hexane. The mixture is stirred at 155C and 200
p~ig for 1 hour. Solvent Neutral Oil SNO-100 (SUS 100) ~1076
parts) i~ then added~ and the hexane is distilled off at
90-120C. The re~ulting solution contains about 8.s w~
polymer,
The proce~ of Example I may be carried out using the
following charge polymer~ of Examples II - IV:
EXAMPLE II
The Epsyn 4006 brand of EPT marketed by
Copolymer containing 58 mole % of units derived from ethylene,
40 mole 4 of unit~ derived from propylene, and 2 mole % of
unit~ deriv-d from ethylidene norbornene and having a ~ln f
120,000 and a MW/Mn of 2.2.
EXAMPLE III
The Ortholeum 2052 brand of EPT marketed by
DuPont containing 62 mole % of units derived from ethylene, 36
mole ~ of unitJ derived from propylene, and 2 mole % of units
derived from 1,4-hexadiene and having a MW/Mn of 2 and a
mol~cul~r weight Mn f 75~000.
--1 1--
1~:71861
60288-2757
EXAMPLE IV
The Royalene brand of EPT marketed by Uniroyal contain-
ing 60 mole % of units derived from ethylene, 37 mole ~ of units
derived from propylene, and 3 mole ~ of units derived from di-
cyclopentadiene and having a Mn of lO0,000 and a MW/Mn of
2.5.
_XAMPLE V*
In this control Example, 100 parts of the same charge
EPM copolymer as used in Example I is mixed with 1076 parts of
SN0-lO0 oil at 80-90C and the mixture i8 agitated under nitrogen
for 24 hours. There is then added phenothiazine (2 parts) dis-
eolved in 8 parts of tetrahydrofuran; and the mixture is maintain-
ed at 80C-90C for one hour.
EXAMPLE VI*
In this control Example, the procedure of Example V* is
followed except that the phenothiazine in tetrahydrofuran is not
added.
EXAMPLE VII
In this experimental example, the procedure of Example I
iB followed except that the polymer i9 EPDM containing 64 mole %
of units derived from ethylene, 35 mole ~ of units derived from
propylene, and l mole % of units derived from 1,4-hexadiene and
having a Mn of 75,000 and a MW/Mn of 2.
- 12 -
X
r 1~ 71~
EXAMPLE VIII
In this control example, the procedure of Example VI
i8 followed except that the polymer employed is the same
polymer as employed in Example VII.
EXAMPLE IX
In this experimental example, the procedure of
Example I is followed except that the functional monomer is
~inJtead of phenothiazine) a monomer prepared by heating for
ono hour a 100C-120C, ~ mixture of eguimolar amounts of allyl
glycidyl ether and phenothiazine.
Tho products of Examples I and V-VIII are subjected
to tho Bonch Oxidatlon Te~t ~BOT) to determine whether the
~dditive is a ~atisfactory anti-oxidant. In the test, an 8.5w~
~olution o~ the te~t polymer in SNO-100 oil is diluted with
~NO-130 oil to give a 1.5w~ ~olution of the test polymer. This
solution i8 heated with stirring and air agitation.
8amples sre withdrawn periodically and analyzed by ~i)
Differential Infrared Absorption (DIR) to observe changes in
the inten~ity of th- carbonyl vibration band at 1710 cm 1, (ii)
the Vl~ual Clarity Te~t and (iii) the Lumetron Turbidity Test.
The Oxidation Index is reported as the Carbonyl Group
Ab~orbance in the Diferential Infrared Spectra after 144 hours
o~ oxid~tion. The Oxidation Index may range from 0 up to 100
and a low rating is desired. The re w lts below 4 are
con~idered excellent.
The cl~ity of the products of Example I and V-IX
i~ al~o reported visuslly and by the Lumetron Turbidity Test
after 144 hours of oxidation. In the Lumetron Turbidity Test,
the turbidity of tho product is determined by a Lumetron
-13-
~ '~ 7~ 8
Photoelectric Colorimeter.
The Lumetron Turbidity is reported on a scale of
S 0-100. A rating of below about 20 is satisfactory; higher
ratings are less satisfactory.
The product of Example I is also subjected to the
standard CEC MWM-B Diesel Engine Test (DIN 51361 Parts I, II,
and IV).
-14-
~ 71 ~61
The following table notes the results - including a
series of tests on a typical commercial formulation.
TA~LE
-
ClaritY at 144 hours
Oxidation LumetronMWM-B
Example Index VisualTurbidity Merits
Commercial 9.5 Turbid 60 53
I 1.1 Clear 14 67
1,0 V 1.8 Turbid 100
V~ 15 Turbid 100
VII 1.3 Clear 12
VIII 16 Turb~d 100
$X 2.1 Clear 16
lS
From the abovo Table, it is apparent that the
experimental ~xample~ I, VII, and IX are characterized by a
de~irably low Oxidatlon Index ~i.e. freedom from oxidation), by
a vi~ually cl-ar readinq, and by a deoirably low Lumetron
Turbidity rating. Control Exampl-~ VI and VIII which fall
out~ido the ~cope of this invention aro characterized by
unde~irably higher Oxidation Indices, by a visually turbid
reading, and by unde~irably high Lumetron Turbidity ratings.
Control Example V iJ un~ati~factory by the latter two
criteria.
Experimental Example I ~howod better deposit
protectlon (higher merit~ in the MMM-~ test) than currently
manufactured commercial di~per~ant olefin copolymer (DOCP)
v~co~ity ind-x improver.
-i -15-
~718~
EXAMPLES X-XI
In Example X, the product of Example I, containing
the functionalized EPM, is tested as a viscosity index improver
in a conventional mineral lubricating oil at concentration of
11 5 w% (corresponding to 1 w% of grafted EPt~); and in control
Example XI , a formulation containing 11 5 w% of commercial
non-dispersant VI improver (corresponding to 1 w~ active
ingredient) in the same system i~ tested
TABLE
Example Kinematic Visco~ity_(cSt) Thickening TP/W%
40C 100C Power el00C Polvmer
15X 58 2 9 89 5 09 0 65
X~ 62 5 10 53 5 60 0 66
Thickening Pow r (TP) is calculated by subtracting
the vi~co~ity o~ the ~ase ~lond (4 8 cSt e 100C) from that of
the te~t ~pecimen measured at 100C This number (e g
9,89-4,8 or 5 09 in the ca~e of Example X) is the Thickening
Power at 100C
Although this invontion ha~ been illustrated by
ref-r-nce to ~peciflc embodiments, it will be apparent to those
sklll-d in tho art that variou~ changes and modifications may
be made which cloarly fall within the w Ope of thi~ invention
