The document introduces Dow Corning's new line of phenyl-fluoro siloxane copolymer lubricants. These lubricants offer improved thermal stability and wear resistance compared to traditional silicone lubricants due to their copolymer structure. Grease and fluid formulations were developed with different phenyl-fluoro ratios to balance thermal stability and wear performance. Testing showed the copolymer lubricants outperformed polyol ester and PFPE lubricants in high temperature performance, corrosion resistance, and wear resistance. The new Molykote G-900x grease series was highlighted as a competitive alternative to PFPE lubricants for applications from -35°C to 220°C.
3. Dow Corning INTERNAL
Polysiloxanes: Structure and Properties
Dimethyl
Silicone
“Standard” silicones H3C –Si – O – Si – O — Si – O – CH3
CH3 CH3
n
CH3
CH3CH3CH3
Phenyl
Methyl
Silicone
Additional thermal
and oxidation stability
H3C –Si – O – Si – O — Si – O – CH3
CH3 CH3
n
CH3
CH3C6H5CH3
Fluoro
Silicone Better load-carrying capacity
and wear resistance
Excellent chemical
resistance H3C –Si – O – Si – O — Si – O – CH3
CH3 CH3
n
CH3
CH3
CH2
CH3
CH2
CF3
3
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Structure of Phenyl / Fluoro Siloxane Copolymer Lubricants
FluoroPhenyl
Thermal stability Wear resistance
Phenyl / Fluoro Copolymer
Different Ph/F ratio allows to
ballance between thermal stability
and wear resistance
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5. Dow Corning INTERNAL
Properties – Thermal Stability
• Samples stored in
an oven at 250°C
• Viscosity measured
weekly / biweekly
until gelling
Sample with high phenyl
content (75:25) has best
thermal / oxidation
stability
Open cup allows evaporation of fluid
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6. Dow Corning INTERNAL
Properties – Thermal Stability
• Samples stored in
an oven at 250°C
• Viscosity measured
weekly / biweekly
• All ratios behave
similarly
• Slight viscosity
decrease
Closed cup prevents evaporation of fluid
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8. Dow Corning INTERNAL
Properties – Wear Resistance of Neat Fluids
T = 50°C
Freq.= 50 Hz
Load = 300 N
Stroke = 2 mm
Cylinder / Plate
Phenylmethyl-
polysiloxane
fluids are not
measureable
(300 N)
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9. Dow Corning INTERNAL
Properties – Wear Resistance of Neat Fluids
Fluid Ph/F ratio 400 N load 800 N load
Average wear scar diameter
Phenyl / Fluoro Siloxane
Copolymer
75:25 1,53 mm
Not
measureable
50:50 1,48 mm 2,82 mm
25:75 0,55 mm 1,81 mm
Polyphenylmethylsiloxane Not measurable
Fluorosilicone 1,18 mm 1,17 mm
4-ball wear scar test (DIN 51350-3)
• 400 N load typically too high for Phenyl-Si-fluids
• Copolymer fluids are able to generate results
• The higher the fluoro content the smaler the wear scars
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10. Dow Corning INTERNAL
Additive Acceptance
Polysiloxane fluids have
limited miscibility with
additives
Fluorosiloxane fluids are
immiscible with additives
Phenyl / Fluoro copolymer fluids show good
acceptance with many commercial available
additives
New lubricants using commercial available
additives
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11. Dow Corning INTERNAL
Lubricity of Fluid
Additives now enable respectable
lubrication performance as
compared to other technologies
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13. Dow Corning INTERNAL
Copolymer Greases
• Greases can be prepared by using single and complex thickener
systems. For example Li- and Li-complex soaps
• Non soap thickerners like polyurea or PTFE are also suitable to
prepare copolymer greases
Grease preparation process is similar
to current polysiloxane greases
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14. Dow Corning INTERNAL
Li-complex Grease (50:50 Ph/F ratio)
Characteristic Test
method
Value
Penetration
(unworked / 60 / 10k / 100k
strokes)
DIN ISO
2137
258 / 261 / 282 /
303
Base oil viscosity (40°C) 246 mPas
Bleed / Evaporation
(24h / 200°C)
ASTM
D 6184
0,46% / 1,17%
Dropping point IP 396-2 340°C
Flow pressure (-35°C) DIN 51805 925 mbar
Emcor corrosion
(7d, dist. water)
DIN 51802 0
Water resistance (3h,
90°C)
DIN 51807 1
DIN 4 ball test (ok-load) DIN 51350 1700 N*
DIN 4 ball test
(wear scar, 400 N, 1h)
DIN 51350 1,05 mm
* Outside DIN measurement range
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15. Dow Corning INTERNAL
PTFE grease (50:50 Ph/F ratio)
Characteristic Test
method
PTFE
grease A
PTFE
grease B
Additivation No additives Additives
Penetration
(unworked / 60 / 100k strokes)
DIN ISO
2137
324 / - / -
290 / 290 /
296
Base oil viscosity (40°C) 790 mPas 460 mPas
Bleed / Evaporation
(24h / 200°C)
ASTM
D 6184
4,58% / 0,44% 3,67% / 0,33%
Dropping point IP 396-2 332°C 285°C
Flow pressure (-40°C) DIN 51805 1125 mbar 950 mbar
Emcor corrosion
(7d, dist. water)
DIN 51802 4 0
Water resistance (3h, 90°C) DIN 51807 0 0
DIN 4 ball test (ok-load) DIN 51350 1900 N* 2300 N
DIN 4 ball test
(wear scar, 400 N, 1h)
DIN 51350 1,02 mm 1,18 mm
FE9 (B, 6000rpm, 1500N,
220°C) F50 value
DIN
51821-2
69h 63h
* Outside DIN measurement range
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16. Dow Corning INTERNAL
The Molykote® G-900X Series Mission
Collaborate with Industry to develop a differentiated line of lubricating
greases based on new patented Phenyl/Fluoro Copolymer technology
from Dow Corning
The Molykote® G-900x series of greases will offer a competitive solution that
enables:
• A lower cost alternative to traditional high cost
lubricants e.g. – PFPE (perfluoropolyether) in some
applications
• Superior performance as compared to Ester based
lubricant technology across a wider temperature range
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17. Dow Corning INTERNAL
Key Features & Benefits
• Heat stability up to 220ºC
• Wide service temperature range (-35ºC to 220ºC)
• Good additive acceptance
• Viscosities (150 cSt to 7000+ cSt)
• Improved wear resistance
• Different Ph/F ratios
• Stable at high Tº in the presence of Lewis acid
• 30% density advantage over PFPE
Cost-in-use advantage
Improved self lubrication at low Tº
Molykote® G-900x is a competitive alternative to PFPE
for high temperature lubrication
PFPEPh/F Si copolymer 18
19. Dow Corning INTERNAL
Test Method Norm, Specification
Silicone
grease
PFPE
grease 1
PFPE
grease 2
PFPE
grease 3
Ester
grease 4
G-9001
(460 mPas)
G-9000
(750 mPas)
Base Oil Technology Ph-Si PFPE PFPE PFPE Polyol-ester Si-Copolymer Si-Copolymer
High temperature
performance: FAG FE9,
(6000 rpm & 1.5kN); F50
DIN 51821 @
220°C
not tested
max service
temp is
200°C
15 h 44 h 42 h 87 h
(@ 180ºC)
62 h 66 h
G-900x Grease offers high temperature lubricity
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21. Dow Corning INTERNAL
Test Method Norm, Specification
Silicone
grease
G-9001
(460 mPas)
G-9000
(750 mPas)
Base Oil Technology Ph-Si Si-Copolymer Si-Copolymer
High temperature
performance: FAG FE9,
(6000 rpm & 1.5kN); F50
DIN 51821 @ 220°C
not tested
max service
temp is
200°C
62 h 66 h
Four Ball Wear Scar DIN 51350 Pt4 /NA 2,61 mm 1,18 mm 1,18 mm
G-900x Grease is a step change in lubricity compared to
standard Si-technology
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22. Dow Corning INTERNAL
Test Method Norm, Specification
Silicone
grease
PFPE
grease 1
PFPE
grease 2
PFPE
grease 3
Ester grease
4
G-9001
(460 mPas)
G-9000
(750 mPas)
Base Oil Technology Ph-Si PFPE PFPE PFPE Polyol-ester
Si-
Copolymer
Si-
Copolymer
Density @ at 20°C ISO 2811 1,05 g/cm³ 1,95 g/cm3
1,95 g/cm3
1,95 g/cm3
1,01 g/cm3
1,42 g/cm3
1,42 g/cm3
G-900x Grease offers 30% density advantage over PFPE
1 kg of Ph/F Si copolymer grease provides
1.3 x more volume compared to PFPE!
PFPEPh/F Si copolymer
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23. Dow Corning INTERNAL
Molykote
®
G-900x performance summary
Test Method Norm, Specification
Silicone
grease
PFPE
grease 1
PFPE
grease 2
PFPE
grease 3
Ester
grease 4
G-9001
(460 mPas)
G-9000
(750 mPas)
Base Oil Technology Ph-Si PFPE PFPE PFPE Polyol-ester Si-Copolymer Si-Copolymer
Density @ at 20°C ISO 2811 1.05 g/cm³ 1,95 g/cm3
1,95 g/cm3
1,95 g/cm3
1,01 g/cm3
1,42 g/cm3
1,42 g/cm3
Consistency DIN 5118 NLGI grade NLGI 2-3 NLGI 2 NLGI 2 NLGI 2 NLGI 2-3 NLGI 2 NLGI 2
Dropping Point DIN 220°C 198°C 169°C 161°C > 295°C 285°C 302°C
Flow Pressure at -40°C Kesternich test 1150 mbar 1175 mbar 700 mbar 575 mbar 775 mbar 950 mbar
1525 mbar (800
mbar @ -35°C)
Bleed after 24H 200°C Fed Stan 791-321.2 9.59% 8.74% 12.28% 10.00% 4,50% 3,67% 3,19%
Evaporation after 24H 200°C Fed Stan 791-321.2 1.75% 0.08% 0.08% 0.14% 2,44% 0,33% 0,36%
High temperature performance:
FAG FE9, (6000 rpm & 1.5kN);
F50
DIN 51821 @ 220°C
not tested
max service
temp is
200°C
15 h 43 h 42 h 87 h @ 180°C 62 h 66 h
Four Ball Wear Scar DIN 51350 Pt4 /NA 2,61 mm 1,45 mm 1,18 mm 0,72 mm 1,03 mm 1,18 mm 1,18 mm
Four Ball Weld Load DIN 51350 Pt4 /NA 1400 N 7500 N > 8500 N > 7500 N 2600 N 2300 N 2300 N
Corrosion resistance: SKF
EMCOR 1week, =<1
DIN 51802 1 0-1 0 1-2 0 0 0
Copper Corrosion ASTM, DC 1b 1a-1b 2b 1b (200°C) 2c 2b (150°C, 3h) 2b (150°C, 3h)
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24. Dow Corning INTERNAL
Applications of Siloxanes as Lubricants
Dimethyl
Silicone
• O-ring and valve lubricants
• Damping grease
• Plastic gears
• Brake caliper
Phenyl Methyl
Silicone
• Overrunning clutch
• Clutch release bearing
• Bearings operating at
low temperatures
Fluorosilicone
• Chemical mixers and pumps
• O-rings or gaskets exposed
to aggressive chemicals
• Brake compressor
• Plug valves
• Circuit breakers
Phenyl-
Fluoro-
silicone
• High-temperature applications (corrugators bearings, oven chains,
automotive powertrain components...)
• Wide service temperature applications (-35°C to +220°C)
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25. Dow Corning INTERNAL
Summary
• Phenyl- Fluoro- copolymer siloxane fluids are a totally new
class of lubricating polysiloxane fluids that opens new
opportunities and possibilities
• Their flexible structure allows to design fluids with high
thermal stability and improved wear resistance properties
• Ph/F copolymer fluids have an improved additive acceptance
which allows to create lubricants for a broad range of
applications.
• Copolymer greases can be prepared with different kind of
thickener systems
• PTFE copolymer greases show excellent thermal resistance at
applications running at high temperatures (>200°C)
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26. Dow Corning INTERNAL
Thank
You
Dow Corning Confidential - INTERNAL The Corning portion of the Dow Corning trademark is a trademark of Corning Incorporated, used under license.