ALKYLATED
I1APHTHALEI1E$
Author:
Maureen E. Hunter, Ph.D.
King Industries, Inc.,
Science Road,
Norwalk, CT, 06852 USA
[email protected]
Greases are used in numerous applications requiring
a broad range of operating temperatures and special
requirements, and the base oil used can impart improved
characteristics to the grease. Alkylated naphthalenes are a
unique class of synthetic fluids with outstanding thermo
oxidative and hydrolytic stability, low volatility, and good
solubility characteristics. The flexibility of this technology
to achieve a balance of physical and chemical properties
will be discussed. Physical property and performance
test data will be presented for both liquid lubricants and
greases with alkylated naphthalenes as the sole base fluid
and as a modifier for other primary base fluids. Grease
work has focused on the advantages of using alkylated
naphthalenes to reduce the amount of thickener, improve
grease clarity and smoothness, and impart significant
resistance to oxidation.
INTRODUCTION
Alkylated naphthalenes are high performance synthetic
fluids that were first developed during WWII but were
never commercialized. In the last 20 years, with advanced
processing technology and raw material availability,
alkylated naphthalenes have emerged as cost-competitive,
high-performance basestocks. These unique synthetic
fluids were first used in engine oils and more recently in
all types of industrial lubricants and greases. They are
primarily used as base oil modifiers with other synthetic
base oils or Group II and III mineral oils. They are used
to enhance the thermal and oxidative stability and/or
additive performance to extend the lifetime of high
performance lubricants. The basic structure of an
alkylated naphthalene is shown in figure 1, where the
core consists of two fused six-membered rings with
the alkyl groups attached. It is because of the ability
of this electron-rich conjugated naphthalene ring to
absorb energy, resonate, and disperse energy, much like
antioxidants do, that alkylated naphthalenes inherently
have excellent thermo-oxidative stability. To make
alkylated naphthalenes, naphthalene is reacted with an
alkylating agent (alcohols, alkyl halides, or olefins) in the
presence of an acid catalyst and this produces a mixture
of alkylated naphthalenes having different numbers of
alkyl groups on the naphthalene ring. The reaction is
shown in figure 2.
The physical properties of alkylated naphthalenes
depend on:
• The number of carbons in the alkyl group, which is
controlled by raw material selection.
• The degree of branching of the alkyl group, which is
controlled by raw material selection.
• The number of alkyl groups on the naphthalene ring,
which is controlled by chemical processing.
Figure 3 shows by gas chromatograph the distribution of
an alkylated naphthalene mixture showing MAN (mono
alkylated naphthalene), DAN (di alkylated naphthalene),
– 26 VOLUME 79, NUMBER 2
NIGI
and PAN (poly alkylated
naphthalene) with three or more
alkyl groups on the naphthalene ring
(1). Table 1 describes the physical
properties of alkylated naphthalenes
made with linear and branched alkyl
groups of the same carbon number
(2). MLAN is a mono linear alkylated
naphthalene, so it has one linear
alkyl group on the naphthalene ring.
MBAN is a mono branched alkylated
naphthalene, so it has one branched
alkyl group on the naphthalene
ring. PLAN is a poly linear alkylated
naphthalene, so it consists of 2 two
or more linear alkyl groups on the
naphthalene ring, and PBAN is a poly
branched alkylated naphthalene, so
it consists of two or more branched
alkyl groups on the naphthalene ring.
From the table, one can see that:
• Viscosity increases with increasing
number of alkyl groups and with
chain branching. So the mono
linear alkylated naphthalene has
the lowest viscosity.
• Viscosity index (VI) increases
with the number of alkyl groups,
and linear alkyl groups have
better viscosity index because it
is easier for them to coil up at low
temperatures and expand at high
temperatures compared to the
branched alkyl chains. Branched
alkyl groups are more rigid
especially at lower temperatures
and this destroys the viscosity
index.
• Pour point increases with
increasing number of alkyl groups
and branching. Mono linear
alkylated naphthalenes have the
best (lowest) pour points.
• Aniline point, which is a measure
of the polarity of a substance
and its ability to solubilize polar
material, increases with increasing
number of alkyl groups but
decreases with branching. The
lower the number the better the
ability to solubilize polar material.
Flash points are good for all. In
the American Petroleum Institute
(API) categories for base oils,
as shown in table 2, alkylated
naphthalenes are part of the
Group V category. Group I, II,
and III are paraffinic oils refined
from petroleum crude oil with
increasing severity of refinement.
Group IV base oils are poly-alpha
olefins (PAO). Group V is the
catch—all for base oils not included
in the other categories. Figure 4
shows the structure of an alkylated
naphthalene compared to other
synthetic lubricants, including a
PAO, a polyol ester, and a diester.
Compared to mineral oils, PAOs,
esters, and polyalkylene glycols
(PAG), alkylated naphthalenes
have several performance
advantages, as shown in table 3.
They provide superior thermo
oxidative stability because of
the electron-rich naphthalene
ring and its ability to resonate
and disperse energy. Alkylated
naphthalenes have inherent
hydrolytic stability because they
do not contain any functional
groups that can hydrolyze. They
have good seal swelling properties
better than Group II and III
mineral oils and PAOs. They have
better additive solubility than
Group II and III mineral oils and
PAOs, and this is again because of
the aromatic ring of the alkylated
naphthalene. They also have
–
– 27 NLGI SPOKESMAN, MAY/JUNE 2015
•
•
•
•
o
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good low pour points and greater
film thickness and film strength,
which can reduce friction. As
previously mentioned, another
property used to characterize
oils is aniline point. This is an
indirect measure of the polarity
of a substance and its ability to
solubilize polar materials. A low
aniline point is indicative of a
fluid with high polarity and good
solubilizing characteristics. As
shown in figure 5, the aniline
point of alkylated naphthalenes
is between esters, which have
high polarity, and mineral oils
and PAOs, which are non-polar.
So alkylated naphthalenes can be
used to help solubilize additives
in non-polar base stocks, and,
like esters, are often added
to PAOs. However, alkylated
naphthalenes do not incorporate
hydrolytic instability or compete
with additives for the surface as
esters can. The mono alkylated
naphthalenes are more polar than
the poly alkylated naphthalenes.
In today’s marketplace, alkylated
naphthalenes are available with a
diverse ISO viscosity range from
22-193 cSt at 40°C, as shown in
table 4. In general, as the viscosity
increases:
Viscosity index increases
Aniline point increases, which
means the solubility decreases
Volatility decreases significantly
Pour point increases
Flash point increases
Oxidative stability remains
excellent
Thermal stability remains
excellent
NLGI
Several alkylated naphthalenes are also approved by the
U.S. FDA for use as Hi “Lubricants with Incidental Food
Contact” per 21 CFR 178.3570, where they can be used
up to 100% if needed to achieve the desired technical
effect. Some are NSF listed as HX-1 additives. The
primary areas of application for alkylated naphthalenes
include:
Automotive and Stationary Engine Oils
o Automotive and Industrial Gear Oils 3
• High Temperature Chain Lubricants
o Paper Machine Oils
• Hydraulic Oils
• Circulating Oils I Turbine Oils / R&O Oils
• Screw Compressor Oils
• Heat Transfer Oils
• Automotive and Industrial Greases
EXPERIMENTAL
In this paper, alkylated naphthalenes are evaluated both
as neat fluids and as base oil modifiers using the following
tests (3).
• Thermal Stability
Federal Test Method 3411
Cincinnati Milacron ASTM D 2070
• Thermo-oxidative Stability
Panel Coker Federal Test Method 791-3462
Rotating Pressure Vessel Oxidation Test (RPVOT)
ASTM D 2272
Pressure Differential Scanning Calorimetry (PDSC)
ASTMD 6186
• Hydrolytic Stability
Beverage Bottle Test ASTM D 2619
• Volatility
• Low Temperature Performance
Viscosity vs. Temperature with VI and PPD
• Friction
FZG ASTM D 5182
• EHD (Elastohydrodynamic) Film Thickness and
Pressure-Viscosity Coefficient
• Seal Swell
Volume Change and Hardness Change ASTM D
4289 and ASTM D 471
• Grease
Pressure Differential Scanning Calorimetry (PDSC)
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ASTM D 5483
RESULTS AND DISCUSSION
Thermal Stability Federal Test Method 3411
In Federal Test Method 3411, samples are held at 274°C
for 96 hours in the presence of a steel coupon in a sealed
glass tube. The test evaluates the change in viscosity,
increase in acid number, steel coupon weight loss, steel
coupon appearance, and appearance of the oil. Table 5
shows that neat samples of AN-iS, AN- 19, and AN-23
did not undergo any significant decomposition using this
test method. A 7 cSt Group III base oil was also evaluated
and compared to 20% modifications with AN-15, a
trimethylolpropane (TMP) ester, and a diester. Table 6
shows that the Group III oil modified with the alkylated
naphthalene exhibited excellent performance while the
oils containing the esters resulted in thick, dark deposits
and, in one case, extensive degradation of the metal.
Cincinnati Milacron ASTM D 2070
–
Cincinnati Milacron testing was also conducted. In this
test, 200 ml of the test fluid is held at 135°C for 7 days
in the presence of copper and steel rods. Measurements
include sludge formation, copper rod rating, steel rod
rating, change in viscosity, and change in acid number.
Even though the test is normally run at 135°C, testing
was conducted at higher temperatures. Table 7 shows
that when tested at 150°C, AN-iS, AN-19, and AN-23
all showed good performance with little change. Table
8 shows the test results at 200°C comparing AN-is to
a PAO blended to the same viscosity. Even though the
sludge was equivalent, the PAO experienced a very high
viscosity increase. At 225°C, table 9 shows that both these
fluids resulted in equivalent sludge, but again the PAO
experienced a very high viscosity increase, even with the
addition of 1.5% of a package containing antioxidants, a
yellow metal deactivator, and a rust inhibitor.
Thermo-oxidative Stability
Panel Coker FTM 791-3462
In Panel Coker testing, oil is splashed against a test
panel at elevated temperatures and the amount of coke
deposited on the panel is determined by weight. As
shown in table 10, modifying a PAO with 10% of AN-8,
– 28 VOLUME 79, NUMBER 2
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NLGI
AN-is, and AN-19 significantly reduced the amount
of coke formed. The neat PAO resulted in 9 mg of coke,
while the PAO modified with alkylated naphthalene
resulted in much less. This is also evident by the pictures
showing the 100% PAO result on the left and the PAO
modified with 10% AN-15 on the right.
combination exhibited good additive response, increasing
the oxidation induction time with 0.2% alkylated
diphenyl amine (ADPA) and alkylated phenyl alpha
naphthylamine (APANA).
Hydrolytic Stability
Beverage Bottle Test ASTM D 2619
In the Hydrolytic Stability Beverage Bottle test, a 75 g
sample, 25 g of distilled water, and a copper test strip are
sealed in a Coca-Cola bottle. The bottle is rotated for 48
hours in an oven at 93°C. Measurements include total
acidity of the water, copper loss, appearance of the copper
strip, and the acid number change of the oil. Two neat
alkylated naphthalenes, AN-is and AN- 19, were tested
and showed excellent hydrolytic stability, as shown in
table 13. As mentioned earlier, alkylated naphthalenes
do not contain functional groups that tend to hydrolize.
Figure 8 shows the beneficial effect of adding 10% AN-iS
to an ISO VG 46 Group II base oil compared to adding
a diester and a poiyoi ester. The esters are hydrolytically
unstable and this results in high acid values of the water
layer.
–
Rotating Pressure Vessel Oxidation Test (RPVOT)
ASTM D 2272
–
RPVOT testing was conducted where 50 g of test
fluid and 5 ml of water with a copper coil catalyst are
pressurize to 90 psi with oxygen and then held at 150°C.
The time required for the pressure to drop to 25 psi is
defined as the lifetime of the sample. Table 11 shows
that neat fluids of AN-15, AN-19, and AN-23 showed
superior thermo-oxidative stability compared to a PAO of
equal viscosity to the AN-is. The alkylated naphthalenes
also showed very good additive response, resulting in
very high RPVOT lifetimes compared to the PAO when
additized with 0.2% of di-tertiary butyl phenol (DTBP)
and alkylated di-phenyl amine (ADPA) antioxidants
versus the PAO. This was especially noted with the ADPA.
The excellent thermo-oxidative stability of alkylated
naphthalene is the result of the electron-rich naphthalene
ring, which can scavenge radicals, resonate, and disperse
the energy. Table 12 shows the AN-8 being used to boost
the RPVOT performance of a Group III oil containing
0.7% of an R&O package. Replacing 15% of the Group
III oil with alkylated naphthalene increases the oxidation
lifetime from 1339 to 1926 minutes but also significantly
reduces the sludge in the Cincinnati Milacron test.
Pressurized Differential Scanning Calorimetry
(PDSC) ASTM D 6186
–
PDSC measures the oxidation induction time to an
onset of an exotherm under specific conditions. Testing
was conducted using 2 mg samples at 500 psi and 160°C.
An ISO VG 46 Group II oil was compared to the Group
II oil modified with 20% of AN-8, AN-is, and AN-i9,
as shown in figure 6. The addition of the alkylated
naphthalene increased the oxidation induction time and
reduced the rate of oxidation. The degree of improvement
depended upon which alkylated naphthalene was used.
Also tested was a PAO modified with 20% AN-8 with
and without antioxidant. Figure 7 shows that the oil
Volatility
Thin film testing was conducted using 2 g of fluid in an
aluminum pan for 24 hours at temperatures of 200°C,
225°C, and 250°C. As shown in table 14, AN-iS showed
less volatility at the lower temperatures than a PAO of
equal viscosity. A second alkylated naphthalene, AN-i9,
also resulted in good volatility. Table 15 shows that a
40 cSt PAO had higher volatility than the AN- 19, and
when 20% of the alkylated napthalene was added to the
PAO, the volatility was brought down to the level of the
alkylated naphthalene alone. For comparison, an ester at
20% in the PAO resulted in significantly higher volatility.
Low Temperature Performance
Viscosity versus temperature profiles were run as shown
in figure 9. The upper line is for an 8 cSt PAO containing
20% viscosity index (VI) improver. When 20% of the PAO
is replaced with AN-8, the viscosity temperature profile is
improved, and further improvement is realized with the
addition of 0.3% of a pour point depressant (PPD). FZG
– 29 NLGI SPOKESMAN, MAY/JUNE 2015
Friction Performance ASTM D 5182
–
In the standard FZG test, gears are run at increasing
load stages at a constant speed of 1450 rpm for 21,700
revolutions (about 15 minutes) per load stage until
scuffing occurs. Figure 10 shows the results of a modified
procedure where the first 6 load stages were run in
accordance to the ASTM method. Then Load Stage 7
was applied for an 8-hour duration and the temperature
difference between the gear box and the room was
determined. AN-is was compared to a mineral oil and
PAO of similar viscosity, each containing 0.3% of an
AW additive. AN-is showed less frictional heat than
the mineral oil and was equivalent to the PAO. EHD
(Elastohydrodynamic) Film Thickness and PressureViscosity Coefficient A WAM machine was used where
a optical interferometer measures fluid film thickness
between a rotating Pyrex disc and a smooth 2 cm free
wheeling steel ball. The load applied was 44.4N, and
optical measurements to determine film thickness were
made at a rolling velocity of 2 rn/sec and temperatures
of 45°C and 100°C. From the film thickness data,
pressure-viscosity coefficients were calculated using the
Hamrock-Dowson formula for point contacts. Pressureviscosity coefficients are a good measure of film forming
capability to protect the metal surface at different speeds
and temperatures in rolling contact zones. An alkylated
napthalene and a polyolester of the same viscosity were
tested, and the film thicknesses and pressure-viscosity
coefficients are reported in table 16. The alkylated
naphthalene resulted in thicker films and superior
(higher) pressure-viscosity coefficients showing better
film forming capability.
Seal Swell Performance ASTM D 4289 and ASTM
D471
–
Neat AN- 19 was tested with three different seal
materials using the ASTM D 4298 test. Table 17 shows
that AN- 19 imparted seal swell to the different elastomers.
Using a nitrile seal material, a 20% addition of AN-iS to
a 7 cSt Group III oil was compared to the Group III alone
using ASTM D 471. Figure 11 shows that the alkyated
naphthalene was able to impart seal swell properties to
the non-polar Group III base oil. Greases Made with
Alkylated Naphthalenes Lithium 12-hydroxystearate
greases made with AN-is and PAO of a similar viscosity
were also evaluated. The grease made with the alkylated
naphthalene had several improved properties over the
grease made with the PAO, as shown in table 18. The
grease made with AN-is required less thickener 7%
compared to 12% for the PAO grease. Less thickener
can result in improved low temperature properties. The
alkylated naphthalene grease was also more transparent
than the PAO grease. This can be seen in figure 12 and
is probably because the alkylated naphthalene acts as a
bridging solvent, reducing the opaqueness of the grease.
The AN-is grease was also a smoother grease than the
PAO grease probably because the alkylated naphthalene
acts as a highly effective dispersant. The AN-is grease
also resulted in superior thermal gravimetric analysis
and PDSC performance, liberating very small amounts of
heat.
—
Pressurized Differential Scanning Calorimetry
(PDSC) ASTMD 5483
–
PDSC testing was conducted using greases made with
the same lithium 12-hydroxystearate thickener but with
blends of different oil ratios of AN-is and PAO. In this
test, 2 mg of grease was place in an aluminum test pan
and the temperature was ramped at 100°C/mm to the test
temperature. Then the sample was allowed to equilibrate
at the test temperature for 2 minutes. The oxygen valve
was opened, and the system was pressurized to 500 psi
within 2 minutes. When equilibrated, the oxygen was
adjusted to a flowrate of 100 ml/min. Note that the
oxidation induction time is measured from the time
when the oxygen valve is opened. Figure 13 shows the
temperature ramp to the test temperature, the 2 minute
equilibration, and the opening of the oxygen valve,
which always causes a spike. Figure 14 shows PDSC test
results at 180°C. The temperature ramp, the 2 minute
equilibration, the oxygen valve opening, and the spike can
clearly be seen followed by whatever happens afterwards.
The grease made with 100% Group III oil was the least
stable and oxidized immediately and quickly. The grease
made with 100% PAO was better but also oxidized
quickly. Modifying the PAO with 10% AN-iS imparted
oxidation resistance to the grease. And modifying the
PAO with 50% alkylated naphthalene imparted significant
oxidation resistance making the grease completely stable
and equivalent to the grease made with 100% alkylated
naphthalene.
30 VOLUME 79, NUMBER 2
CONCLUSIONS
So why use alkylated naphthalenes? Alkylated
naphthalenes are high performance synthetic fluids
available in a diverse ISO viscosity range from 22-193
cSt for flexibility in designing lubricants for specific
applications. They have many superior performance
properties over other oils and are able to impart these
advantages when added to other oils and greases. They
provide excellent thermal and thermo-oxidative stability
because of the electron-rich naphthalene ring and
its ability to resonate and disperse energy. Alkylated
naphthalenes have inherent hydrolytic stability because
they do not contain functional groups that can hydrolyze.
They have good seal swelling properties better than
Group II and III mineral oils and PAOs. They have better
additive solubility than Group II and III mineral oils
and PAOs and less surface competition than seen with
polar esters. Alkylated naphthalenes have good pressureviscosity coefficients, film thickness, and film strength,
–
which can reduce friction. They also have good low pour
points. Greases made with alkylated naphthalenes also
have several advantages over greases made with PAO,
including less required thickener, improved transparency,
and a smoother texture. Alkylated naphthalenes also have
superior thermo-oxidative stability than PAO and are
able to impart this stability to PAO greases.
REFERENCES
1. Hourani, M.J., Hessell, E.T., Abramshe, R.A.,
and Liang, J.G., “Alkylated Naphthalenes as
High Performance Synthetic Fluids,” Tribology
Transactions, 50: 82-87, 2007.
2. Hessell, E.T. and Abramshe, R.A., “Alkylated
Naphthalenes as High Performance Synthetic Fluids:’
Journal of Synthetic Lubrication, 20-2, 2003.
3. ASTM Annual Books of ASTM Standards, Volumes
05.01, 05.02, and 05.03, Petroleum
Figure 1: Alkylated Naphthalene Structure
The core naphthalene system consists
of two fused six-membered rings with a
electron rich conjugated it system.
Ri to R8 are independently a linear or branched
alkyl group or hydrogen
R6
R4
Figure 2: Alkylated Naphthalene Synthesis
Physical properties depend on:
Number of carbons in the alkyl group (Controlled by raw material selection)
Degree of branching of the alkyl group (Controlled by raw material selection)
Number of alkyl groups on the naphthalene ring (Controlled by chemical processing)
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NLGI
Figure 3: Gas Chromatography ofan Alkylated Naphthalene Mixture Showing the Distribution
GC separates compounds by boiling point.
Designation
MLAN
MBAN
PLAN
PBAN
Alkyl Group Structure Number Alkyl Groups
Linear
1
Branched
1
Linear
2-4
Branched
2-4
TyIlcal Properties
Kinematic Viscosity @40 C (cSt)
Kinematic Viscosity @100 C (cSt)
Viscosity Index
Pour Point (°C)
Aniline Point CC)
FlashPoint(°C)
18.2
24.2
NAN
110.5
3.4
3.5
12.8
-36
110
-30
20
-54
1.8
>200
-9.2
>200
Table 1: Physical Properties ofAlkylated Naphthalenes
Linear and branched alkyl groups are of the same carbon number.
– 32 VOLUME 79, NUMBER 2
94
274
PBAN
1050
23
3
42
214
NLGI
Base Stack Group
Sulfur,
~wt. %
Group I
~
Group II
~O~.O3
Group III
~ 0.03
S~tur~tes~
wt%
and/or
80
—
and
Viscosity
Index
119
~
~ GO
~ 90
~ 120
Group IV
All Poly-Aipha-Olefins (PAOJ
Group V
All Base Stocks Not Included in Groups I —IV
Table 2: API Base Oil Categories
Group I: Solvent refined paraffinic base stocks
Group II: Mildly hydrotreated paraffinic base stocks
Group III: Severely hydrotreated paraffinic base stocks
Group V: Esters, glycols, silicones, alkylated aromatics, phosphate esters
I
AIRyIat~ Na$itha1can~
PAO
PoIy~ Es~T
Dl~s~r
Figure 4: Generalized Structures ofAlkylated Naphthalenes vs. Other Synthetics
33 NLGI SPOKESMAN, MAY/JUNE 2015
NLGI
Mineral Oils
PAO
(Group II & ifi) (Group IV)
Thernio-Ox
Stability
Thermal
Stability
Hydrolytic
Stability
Esters
PAGs
Alkylated
Naphthalenes
Good
Good
Fair to Exc~
Good
Excellent
Excellent
Excellent
Excellent
Excellent
Excellent
Excellent
Excellent
Poor to Good
Excellent
Excellent
Seal Swell
Poor
Poor
Excellent
Good
Good
Viscosity
Index
Additive
Solubility
Good
Excellent
Excellent
Excellent
Good
Fair to Poor
Poor
Excellent
Good
Excellent
Pour Point
Good
Excellent
Excellent
Excellent
Good
Film
Thickness
Fair
Good
Good
Good
Excellent
Table 3: Comparison of Some Lubricant Base Fluids
Less Polar
More Polar
4O~55DC
-7 to 5C
u-iorc
11s-1wc
— 4vr
~_n
—
Monaestm~
DIe~tor~
[~ANJ
Group II
Group Ill
Mineral OlIn
FigureS: Aniline Point
– 34 VOLUME 79, NUMBER 2
NLGI
~ROPERTY
AN-7A
AN-8
AN-9
AN-15
AN-19
AN-23
?iscosity ~ 40°C
218 cSt
36 cSt
37 cSt
114 cSt
177 cSt
193 cSt
Viscosity @ 100°C
18 cSt
56 cSt
5J cSt
13i cSt
183 cSt
198 cSt
22
90
91
110
118
118
Aniline Point
40°C
42°C
50°C
94°C
103°C
NA
~oack Volatility, by wI
39%
12%
73%
Z2%
5520
1098
—
182
136
0A2
-48°C
-33°C
-33°C
-39°C
-26°C
-21°C
236°C
>250°C
260°C
285°C
310°C
Viscosity Index
O:~~7~oC
E~our Point
Flash Point
<
206°C
Table 4: Alkylated Naphthalene Properties
[
Ar~1-15
AN-i9
AN-23
+0.6%
0
f0.7%
0
+0.1%
0.02
0
0
~0.02
+0.017
Dull Brown
None
Light Yellow
Light Yellow
Clean
±0.034
Dull brown
None
Ll~ht Yellow
Light Yellow
Clean
+0.033
Dull Brown
% Change in Kinematic Viscosity (~ 40°C
Initial Acid Number (rrig KOHfg)
Change in Acid Number
Change in Metal Weight ~mg/cm2)
Appearance of Metal
Sediment
OrigInal Oil Appearance
Final Oil Appearance
Test Cell Appearance
Table 5: Thermal Stability (FTM 3411)
274°C for 96 hours with steel coupon in sealed glass tube
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35
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NLGI SPOKESMAN, MAY/JUNE 2015
None
Yellow
Yellow
Clean
Table 6: Thermal
Stability (FTM
3411)
274°C for 96 hours
with steel coupon in
sealed glass tube
A 7 cSt Group III
base stock has been
modified with dif
ferent Group V base
stocks.
7 cSt Group
% Change In Kinematic
Viscosity at4ODC
Change in Acid Number
m
20% AN.15
80% 7 cStGroup Iii
20% TMP Ester
80% 7 cStGroup Ill
2035 Diester
BO%7 cSt Group III
~
0.03
6.0
0
Change in Metal Weight~
(mglcm2)
0.3
.~
Appearance of Metal
Gold
Shiny
Stilny
Etched
Final Oil Appearance
Clean
Llgt# Amber
Black
Test Cell Appearance
Clean
Clean
Heavy Black
Stains
% Vist~nsity Change
Biue-Biacl~
Amber
Clean
_____
AN-IS
AN-19
AN-23
IS
2~i
4M
Acid Number Change (rngKOHIg)
&03
0.03
0.02
Total Sludge (mgIiOOml)
0.55
0.65
0.50
CM Color Class Copper
2
3
2.5
~
–
Table 7: Thermal Stability Mod~fied Cincinnati Milacron ASTM D 2070
Copper and steel rods in 200 ml test oil (Test run at 150°C, 7 days)
Original test procedure is run at 135°C, 7 days.
–
Table 8: Thermal Stability Modified
Cincinnati Milacron ASTM D 2070
Copper and steel rods in 200 ml test oil
(Test run at 150°C, 7 days)
Original test procedure is run at 135°C,
7 days.
* PAO is 114 cSt @ 40°C
Blend adjust
Neat Fluid
–
–
ed to equal viscosity of AN-15.
Total Sludge
(rr~/1OOn1)
AN-15
_____________
PAO*
___________
______________________
2~8
2~i
___________________
% ViscosIty
Increase
e
100
Base Fluid with 1.5% ADP~ © 225CC
Total Sludge
% Viscosity
~m~11 G0n~)
Increase
8.1
20
8.1
164
Neat Fluid
% Viscosity
Total Sludge
~rn~I1 00ml~
1~.9
13.6
AN-15
PAO~
20
332
–
–
Table 9: Thermal Stability Modified Cincinnati Milacron ASTM D 2070
Copper and steel rods in 200 ml test oil (Test run at 150°C, 7 days)
Original test procedure is run at 135°C, 7 days
** PAO
114 cSt @ 40°C Blend adjusted to equal viscosity of AN-15.
*** Additive Package containing antioxidants, yellow metal deactivator, and rust inhibitor.
–
–
–
100% P!40
(ISO VG 220)
10% AN4
90
to
Coking Value (mg)
90% PAO
10% AN-IS
9’J% PAD
10% At41~
1)0% PAD
20
Table 10: Thermal Stability Panel Coker FTM 791-3462
Temperature Conditions:
Test Panel: 200°C
Oil Sample: 140°C
–
Umln~)n~tfhild
Table 11: Thermo-oxidative
Stability RPVOT ASTM D 2272 Lifetime (minutes) with
9,2% Phenoii~AO Llfethne (minutes) wIth
O.2%Aml~I~AO -AI~PA
–
PAO~
P.11-15
AN-ID
AN-23
19
87
89
191
44
179
21)4
241
34
4119
532
~21
37
NLGI SPOKESMAN, MAY/JUNE 2015
NLGI
Formulations
T.st~
RPVOT(ASTM D 2272)
Ufelinie, miriAes
CM Tilemial S~bIfty (ASTU D 2070)
VisøoyC~r~e(%)
Acid NwrterChar~e (mgKOWg)
Cor~il~on of S~eI Rod Color
Deposlt(mg)
Metal Loss (rrig)
CondI~onofCopperRad:
Depasit(mg)
Metal Loss (mg)
Total SlLiige (rngft00 rrfl)
0,7~6 R&O Package
99~3% GnLp III
OJ% R&O Package
15,0%AN.8
84~% Gro~ Ill
1339
1926
0.19
0.00
2
0.40
0.93
0.01)
2
120
02]
5
0.60
010
5~3~
0.30
Co’or
5
0.50
0.40
1DZS
Table 12: Group III (ISO VG 46) vs. Group III Modified with Alkylated Naphthalene
Figure 6: Thermo
oxidative Stability
PDSCASTMD 6186
Isothermal @ 160”C,
500 psi Oxygen
Group II vs. 20%
Alkylated Naphthalene
in Group II
–
Time (n1~n)
– 38 VOLUME 79, NUMBER 2
NLGI
Figure 7: Thermo
oxidative Stability
PDSCASTMD 6186
Isothermal @ 160CC,
500 psi Oxygen
20% AN-8 in PAO 4 cSt
with 0.2% Antioxidant
—
V4 r,~. T.’~ ~
Twn~ ~n~fr,)
AN-I 5
AN-I 9
002
LLO2
Hydr&yth StabO~ty(ASTM D 2619)
TAN ~ncxea~e (mg KOWg~
Table 13: Hydrolytic Stability Beverage Bottle Test ASTM D 2619
Neat Alkylated Naphthalenes
–
Figure 8: Hydrolytic Stability
Beverage Bottle Test ASTM
D 2619
Group II Base Oil (ISO VG
46) Modified with 10% of
Different Group V Base Stocks
–
I
~AN-15
Q Utester
~PoIyoI Ester
1a%AN-1~
Gi~
ffl%Diest~r
~G% Graup
– 39 NLGI SPOKESMAN, MAY/JUNE 2015
1U%PdyoIEs~r
~U% Gr~p I~
r~~t FIu~d WeI~ Loss, %
25O~G
225~C
2OO~G
1~-16
12~O
26.7
67.4
IPA0~
411
50.6
85.1
PAO ~s 114 cSt@ 40CC Blend adjusted to equal ‘~iscosi1yofAN-15
Table 14: Thin Film Volatility
2 grams in aluminum pan for 24 hours
–
*
–
Table 15: Thin Film Volatility
2 grams in aluminum pan for 24 hours
W&øh~ La.s. %
Ai~~
PAO4O
20% AN-191 80% PAO 40
20% Ester I6~% PAO4O
2OO~G
22WC
2&0~G
L5
17.S
~19~7
4t$
29~$
9.4
20.2
26.5
43~1
45.4
39.6
56.7
Viscosity vs. Ten~30rature for AN-a (6 cst) In PAO 8 cSt Oil
• 20%
Figure 9: Low
Temperature
Viscosity Profile
40
VI Improver + 80% PAO
20% VI improver ÷ 60% PAO + 20%
AN-8
20% VI improver÷60%PAO
÷ 20% AN-B ÷ 0.3% PPD
30
20
10
0
-35
-30
-25
-20
Temperature {0C)
– 40 VOLUME 79, NUMBER 2
-15
-10
-5
1201
Figure 10: Friction Study
FZG Modified ASTM D
5182
Test Oils with 0.3% AW
additive
–
~,
~j
I
Ii
~
~
~i-1
~
11
ILL IL IL
Mineral Oil
v1~ity ~ 4o~’c ~c8I~
V~o~4ty ~ 1O4Y~C {cSi~
V.L:
PAO
AN.U
124~1
1t4~5
14~
110
12~C
fl
r
L~f $t~e~ 14 ~erc nm in
aci~ürdan~ b~ASTM 1)51*2.
Load St~e 7 wa~ applkd für ün
$,~
F
Table 16: EHD Film
Thickness and PressureViscosity Coefficient
EHD FHm Thk,knu~s at 2 mfs~ ai,d
4c5t
PDlyaI
Ester
rim
170
4c~St
AN
40
52
GPa
GP~
rim
225
45~C
~HD Film Thickness at 2 m!sec ~nd
1oo.~c
Pressure-Vlscosfty Ccet’flcient et 2
8.5
m/seoand45~C~
Pressure-ViscosJty CoefficIent at 2
3.9
mfseo and 1OO~C
Table 17: Seal Swell ASTM D
4289 (Neat AN-19)
Volume
Change
–
—~
—
Chioroprene
@1OO~C~ 240 hours
Fluorocarbon
@15O~C~ 240 hours
NitrHe Butadiene
@150~C~ 240 hours
–
41
15,6
7.5
Hardness
Change (points)
____
—______
–
NLGI SPOKESMAN, MAY/JUNE 2015
11.2%
01
–
2
–
–
NLGI
2.50%
200%
~
150%
tOO%
0.50%
~
000%
Figure 11: Seal Swell
-ASTMD 471
~050%
;~
1~V%
4 00%
Table 18: AN-15 vs. PAO 10
in Li—12-OH Grease
Lithium 1 2-Hydroxystearte
NLGI #2
Chioroprene
@iOODC~ 240 hours
Fluorocarbon
@15O~C~ 240 hours
NitrHa Butadiene
~15ODC~ 240 hours
– 42 VOLUME 79, NUMBER 2
Vn1u~
Hardness
Change
Change (points)
112%
-5
01%
-2
3~8%
-1
Figure 12: Grease Color/Appearance
Alkylated Naphthalene
Less thickener = improved low temperature
properties
Bridging solvent = reduced opaqueness
Effective dispersant = smooth grease
O~w~ ~
Figure 13: Thermo-oxidative
Stability PDSC ASTM 5483
Explanation
–
‘
—L~12-QR! 1QO%
Group
I
I~
/
Figure 14: Thermo-oxidative
Stability PDSC ASTM D 5483
at 180”C
Li-12-OHI 1O%AN~15~-~% PAD
–
U-12~OH I 50%AM-15+ &I% PAD
‘~4J~12~Oh/ 1O4~%AN~15
Up
11m~ (m~fl)