SHRIEVE Products International Ltd

R744 compressor lubricantR744 compressor lubricantZerol RFL-EP

(Terminating Alkyl - commonly Me)

Homo-polymer :R

O

O

y

R

Common Capped PAGs -Air-conditioning (mainly Auto HFC)

“Symetrically” Capped PAGs:

R

O

O

R

y

O

y

(Terminating Alkyl - commonly Me)

Random Co-polymer :

y

(Most commonly terminating R = Initiating R,

as both ends simultaneously capped)

Common Capped PAGs -Refrigeration / Air-conditioning (HFC)

“Zerol RFL” capped PAGs ( novel asymetric type) :

Homo-polymer

(Terminating Group - hydroxyl)O

O

y

HO

(Terminating Alkyl - commonly Me)

y

O

O

y

RO

Terminating R ≠≠≠≠ Initiating R

Common Uncapped PAGs -Air-conditioning (mainly Auto HFC)

eg. Zerol PAG

Water Insoluble:

(Terminating Hydroxide)

Homo-polymer

R

O

O H

x

(R - most commonly Me, Bu)

Homo-polymer

Random Co-polymer

R

O

O

H

y

O

y

(R - most commonly Me, Bu)

(Terminating Hydroxide)

Water Soluble:

Capped PAG Comparison

H3C

O

O

y

CH3

Symetrically capped PAG

O

O

y

O CH3

Asymetrically capped PAG

• Zerol PAG Grades : Uncapped PAGs for HFC

• Zerol RFL : Capped basefluids for HFC & R744

Product Grade SummaryProduct Grade Summary

• Zerol RFL-X : Additised capped PAGs for HFC

• Zerol RFL- EP : Additised capped PAGs for R744

Main Performance advantages of asymetrically capped PAGs

(compared with symetrically capped PAGs and uncapped PAGs)

Improved refrigerant miscibility

Enhanced Extreme Pressure / Antiwear properties

Reduced water Absorption

Asymetric capped PAG -CO2 miscibility property.

Miscibility with CO2 enhanced compared with uncapped andsymetrically capped PAGs.

Viscosity reduction associated with miscibility minimal compared with POE.compared with POE.

Lubricity property not disadvantaged by improved miscibility.

Asymetric capped PAG -lubricating property in CO2 systems.

Trans-critical CO2 systems - higher load-bearing requirements.

Falex Block-on-Ring procedure:

Load steps: 50lb steps, followed by 20lb stepsRotation: 600 rpmAtmosphere: CO2

Overpressure: 10 bar (150psi)Step duration: 5 minutesTemperature: 90ºC minimumRing / Block: Steel

Capped PAGs -lubricating property in CO2 systems.

Falex Block-on-Ring Summary:

300

350

400

450

500

Competitor

dicapped PAG

for CO2

Zerol RFL-X (for

Failure Load(20 load steps)

0

50

100

150

200

250

300

Test sample

Zerol RFL-X (for

HFC systems)

Zerol RFL-EP

(For R744

systems)

Capped PAGs -Lubrication in CO2 systems - Block wear.

Competitordicapped PAG

(Symetric capped)

Zerol RFL-X(for HFC)

Zerol RFL-EP(for R744)

50lb load steps50lb load steps

50lb load steps

20lb load steps 20lb load steps 20lb load steps

0.5

0.6

We

ar

Sc

ar

(mm

)

C ompet it o r d icapp ed

Capped PAGs - lubricating property in CO2 systems.

Wear Property of Capped PAGs by falex pin & V-block.CO2 (1 atmos), 100°C:

0

0.1

0.2

0.3

0.4

200 400 600 800

Load (N)

We

ar

Sc

ar

(mm

)

C ompet it o r d icapp ed

PA G

C ompet it o r d icapp ed

PA G - ISO 10 0

Z ero l R F L 4 6 EP

Z ero l R F L 10 0 EP

Capped PAGs - thermal stability property

High Pressure Differential Scanning Calorimetry:

CO2 environment: (1100 Kpa)Temperature: 0 - 350 ºC

Capped PAGs - thermal stability by PDSC in CO2 systems.

SAMPLE START POINT (˚c)

PEAK (˚c) END POINT (˚c)

Zerol RFL 4EP 199.9 215.2 273.8

Competitor ISO 193.9 207.3 270.1 Competitor ISO 46 dicapped

PAG

193.9 207.3 270.1

Zerol RFL 100EP

191.7 208.1 227.6

Competitor ISO 100 dicapped

PAG

182 201.9 285.1

Capped PAGs - chemical stability property

Non-reactivity of PAG with water, hygroscopicity non-problematic.

PAGs non-reactive with any carbonic acid formed by reactionof CO2 with water. Carbonic acid further to SGT typically non-detectable.

Tendancy of PAGs to absorb water is reduced as a result of end-capping.

ASHRAE 97 – 14days, CO2, 175ºC, 0.1wt% H2O.

TAN (unreacted) MgKOH/g

TAN reacted MgKOH/g

Sample

Zerol RFL-EP

0.12 0.01

Zerol RFL-EP + 0.1wt% H2O

0.12

0.01

PAGs as Condensing Compressor Lubricants

HYGROSCOPICITY

PAG water absorption problematic?

Corrosion?

Freezing within capillaries?

Chemical stability?

POE requires:

Low water spec

For chemical stability.

Not required for PAG.

R

O

O

O

O

R

HO

HH

O

H

HO

HH

O

H

Water ‘Chemically’ bound and therefore undesired effects of water not experienced.

Hygroscopicity Comparison –Competitor vs RFL 100EP

2000

2500

3000

Water Content (ppm)

0

500

1000

1500

0 30

120

360

1440

Zerol RFL 100EP

Competitor

Time (mins)

Zerol RFL-EP / Competitor Compatibility

• RFL-EP & competitor dicapped PAGs fully compatible

over the full temperature range tested (-20 to +110°C).

• Fully compatible in all proportions (0-100% either component).

• All samples remain clear and homogeneous.

Conclusions

• Novel capping technology:-enables the synthesis of PAG type refrigeration lubricants with application specific properties, eg. R134a and CO2 compressor applications.

• Flexible “capping” process:allow structure modification and hence performance optimisation for the future refrigerant technology developments.

Zerol Capped PAGsFreedom / Availability to Use

• Worldwide patented “Asymetric Capped PAG” technology

• Non-infringing of competitor patents for HFC systems

• Worldwide freedom to supply for both HFC and CO2 systems

• Manufactured UK, delivered worldwide.