Organic friction modifiers in engine oils – Fatty amines and fatty amine ethoxylates Sarah Lundgren Tribo Days 6-8 November 2012

Organic friction modifiers in engine oils –Fatty amines and fatty amine ethoxylates

Sarah LundgrenTribo Days 6-8 November 2012

Petroleum and Water applications

Overview

- What is AkzoNobel Surface Chemistry’s Fatty Amine Chemistry

- Ongoing investigations

- Friction and wear of fatty amines and fatty amine ethoxylate

- Summary

AkzoNobel’s position in the Lube Oil Additive Market

Surface Chemistry | Lubes & Fuels 3

AkzoNobel Surface Chemistry Fatty Amines Process Overview


Fat Splitting

Distillation

Nitrilation Hydrogenation

Esterification Quaternization

Alkoxylation

Oxidation

Arquad®Ethoquad®Armosoft®

Armolube T®

Ethomeen®Propomeen®

Ethomid®Ethofat®

Armeen®Duomeen®Triameen®

Raw Materials:Animal Based Fats

Vegetable Based Oils

Half Crude Gly.

Oxidation

Armid®Amidation

Aromox®

Neo-Fat®



A world of Fatty Amine Derivatives

Triamine

Tetraamine

EthomeenPropomeen

DuomeenTriameenTetrameen


R NH NH2

Diamine

Duomeen T

R N N

CH3

CH3

CH3

Trimethyl diamine

Duomeen TTM

R N+

N+

CH3

CH3 CH3

CH3CH3

R NH NH2

R N N

OH

OH

OH

R NH2

+NH3

+

R N+

N+

OH

OH

OH

CH3 CH3

Cl

Cl

O R'

O

2 2

2

Ethoxylated diamine

Diquaternary

Ethoxylated diquaternary

Diamine salt

Duomeen TDO

Diamine Chemistries

Also ethoxylate di, tri and tetra amine chemistries


Fatty chain

N

OH

OHFatty chainTallow, oleyl, coco, and erucyl

Coco (12) Tallow (18) Erucyl (22)

Oleyl (95%) Tallow (46%) 18 (0%)

Longer chain

Less unsaturation


Ongoing research

Two long term investigations in-house

• Screening of existing products (catalogue) and new in the MTM in combination with ZDDP only

• Fundamental understanding of friction modifiers in oil – both in bulk and at surfaces

Many additives in an oil and a lot interactions taking place.

Beginning with interactions of amine friction modifiers and antiwear additive ZDDP


Samples

• A primary / secondary blend of ZDDPs (0.5wt%)

• Group III base oil from Nesteoil

• 0.5wt% FM

Petroleum Applications

Background ZDDP

Distribution of ZDDP antiwear film

Steel surfaceZinc Sulphide

ZnS

(Poly)phosphate

Alkyl phosphate precipitates• Long

chains• Short

chains

10-100nm150nm

Patchy film

Properties – hardness

Chemical composition(3)

• Increasing hardness closer to the surface

• Alkyl phosphate precipitates rinse off with solvent.

81GPa25GPa

90GPa

25-40GPa

(1) Warren et el, Trib. Letters, 4 (1998) 189(2) Graham et al. Trib. Letters 6 (1999) 149; Nicholls et al. Trib. Internat. 38 (2005) 15(3) Bec et al. Proc. R. Soc. London, 455 (1999) 4181

12

Techniques for measuring friction and wear

Oil Film Thickness/Surface Roughness (or N/P)

Bou

ndar

y lu

bric

atio

n

Mix

ed

lubr

icat

ion

Hydrodynamic lubrication

Fric

tion

Coe

ffici

ent

Valve Train

Piston Rings

Journal Bearings

Steel DiscSteel Ball

Lubricant


Techniques

Minitraction machine (MTM) with film thickness measurement

• The MTM is run with 120C, 20N and a slide roll ratio of 50%.

• Measure at constant speed (200mm/s), load and temperature for two hour but stop for Stribeck curves at 0, 15, 30, 60 and 120 min.

• A lot of data, here we show the Stribeck curve after two hours and the friction vs time curves.

High frequency reciprocating rig (HFRR)

• The HFRR is run at 120 C, 400gram, 50Hz with stroke length of 1mm.

• Here we report wear scar data.

Time

µ


Changes backbone and head group

- Adding methyl groups to an amine increases the friction.

- Secondary amine performs worse than primary.

- It is worse to change the head group than the hydrocarbon chain. Perhaps two chain per molecule helps with the packing.

RNH

R

Secondary amine


Number of EO groups and comparison to PO groups

Increased degree of ethoxylation increases the friction.

Propoxylate worse than ethoxylate.

Not all friction modifiers reduce friction compared to ZDDP.

R N

OH

OH

R N

OH

OH

R N

O

O

H

H

m

n


R NH NH2

Diamine

Number of amines

R N N

CH3

CH3

CH3

Trimethyl diamine

Increasing from one to two amines increased the friction.

Methyl groups on diamine increases friction.

Salt of oleic acid and diamine better than only diamine.

Three amine groups performs really well.R N

+N

+

CH3

CH3 CH3

CH3CH3

R NH NH2

R N N

OH

OH

OH

R NH2

+NH3

+

R N+

N+

OH

OH

OH

CH3 CH3

Cl

Cl

O R'

O

2 2

2

Ethoxylated diamine

Diquaternary

Ethoxylated diquaternary

Diamine salt


Film thickness

All friction modifiers reduce the antiwear film thickness.

A thin film usually provide low friction.

A disturbance in the antiwear film formation does not have to result in increased wear.

ZDDP 311µmArmeen DMTD 242µm

Duomeen T 197µmEthomeen T 219µm

Armeen T 246µm


Summary

- ZDDP anti wear films show high friction giving a negative effect on Fuel Efficiency.

- Early work suggests that optimal choice of Fatty Amine Chemistries can bring benefits in reduction of friction and film thickness

-Most amines tested reduce friction in boundary and mixed

-Methyl Groups on amine and diamine and Ethoxylates on amine perform worse than only amine. Two hydrocarbon chains worse than one. But changing head groups worse than fatty chain.

-Diamines show an increase in friction compared to primary Amines. Adding oleic acid to diamines is better than without.

Triamine show better performance than primary amine and this product is the best performing candidate presented.

All FMs lower the film thickness compared to ZDDP. However, this does not result in poorer wear protection.


Thank you for your attention!

Documents

Organic friction modifiers in engine oils – Fatty amines and fatty amine ethoxylates Sarah Lundgren Tribo Days 6-8 November 2012