new silicone copolymer lubricants


Topics

• Siloxane Copolymer Technology

• G-900x Series Greases

• Technology review

• Applications

2


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 stabilityH3C –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

CH2CH3

CH2

CF3

3


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

4


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

5


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

6


Properties – Comparison

Fluid Ph/F

75:25

Ph/F

50:50

Ph/F

25:75

PAO

40

Polyol-

ester

Silicone

fluids

(PMPS)

Fluoro-

silicone

PFPE

(branch

ed)

PFPE

(linear)

Viscosity

(40°C), mPas408 328 314 345 171 244 188 80 cSt 159 cSt

Viscosity Index 229 239 242 155 145 220 241 108 338

TGA (250°C) 98,6% 99,0% 99,0% 97,4% 96,5% 99,1% 97,2% 93,4% 99,3%

DSC (onset

temperature)282°C 283°C 277°C 205°C 203°C 366°C 246°C 348°C 330°C

Evaporation

(200°C, 7d)0,13% 0,47% 0,65% 7,85% 13,38% 1,46% 18,50%

Not

tested

Not

tested

TGA and DSC: 30-500°C, 10°C/min, air 60ml/min

Evaporation: internal test method (open cups in oven)

• Viscosity indices 230 – 250

• TGA: ≈ 99% of material remains at 250oC

• DSC onset temperatures > 270oC

• Low evaporation at 250oC

7


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)

8


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 mmNot

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

9


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

10


Lubricity of Fluid

Additives now enable respectable

lubrication performance as

compared to other technologies

11


Topics




• Applications

13


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

14


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 61840,46% / 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

15


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

2137324 / - / -

290 / 290 /

296

Base oil viscosity (40°C) 790 mPas 460 mPas

Bleed / Evaporation

(24h / 200°C)

ASTM

D 61844,58% / 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

51821-269h 63h

* Outside DIN measurement range

16


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

17


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 copolymer18


Topics




• Applications

19


Test Method Norm, SpecificationSilicone

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

21


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)


Corrosion resistance:

SKF EMCOR 1 week,

dest. water

DIN 51802 1 0-1 0 1-2 0 0 0

G-900x Grease offers corrosion resistance

22



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

23



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-esterSi-

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

24


Molykote®

G-900x performance summary


grease

PFPE

grease 1

PFPE

grease 2

PFPE

grease 3

Ester

grease 4

G-9001

(460 mPas)

G-9000

(750 mPas)


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 mbar1525 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, =<1DIN 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)

25


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)

26


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)

27


ThankYou

Dow Corning Confidential - INTERNAL The Corning portion of the Dow Corning trademark is a trademark of Corning Incorporated, used under license.

new silicone copolymer lubricants

Engineering