Krytox® Vacuum Pump Fluids

PRODUCT INFORMATION
DuPont™ Krytox® vacuum pump fluids are used in 
applications where conventional vacuum pump oils cause 
safety, waste disposal and maintenance problems. They 
are nonflammable and eliminate the chance of fire in 
pumps. They are nonreactive and safe to use in oxygen 
systems. They can replace competitive PFPE fluids as 
well as any other type of vacuum fluid. Krytox® fluids do 
not contain acetal groups, which are susceptible to attack 
by Lewis acids. (See Figure 2 and Table 4.) This gives 
Krytox® superior stability as a vacuum pump fluid. Krytox®
vacuum fluids are precisely distilled to provide low vapor 
pressures and give superior performance. (See Figure 1.) 
In addition, Krytox® fluids are recyclable.
Krytox® XP VPF oils contain a soluble additive to prevent 
rust. This patented additive enhances the performance 
of Krytox® VPF fluids, giving them improved performance 
properties. The long-term antirust properties repel 
moisture, providing extra protection from corrosion of 
metal parts and bearing surfaces.
While Krytox® VPF fluids are inert and nonreactive to all 
elastomers, plastics and metals, the soluble additives in 
the XP products have not been tested with all materials. 
Initial testing has shown no problems with DuPont™
Teflon®, Kalrez®, Viton®, nitrile and silicone rubbers. The 
performance of the soluble additives could degrade at 
temperatures more than 182 °C (360 °F) over a long 
period of time. 
High-Vacuum Grease
Krytox® LVP is high vacuum grease formulated with a 
special low vapor pressure Krytox® oil for high-vacuum 
applications. It is also useful for sealing laboratory 
glassware connections and as a thread lubricant/sealant.
For more information on Krytox® LVP, see Table 3.Table 1
DuPont™ Krytox® Vacuum Pump Fluids* 
Test DuPont™ Krytox®
Property Method Conditions Units 1506/1506XP 1514/1514XP 1525/1525XP 1531/1531XP 16256 1645
Average Molecular Weight NMR 2160 2840 3470 3940 9400 NA
Vapor Pressure** Knudsen 20 °C (68 °F) torr 4 x 10–7 2 x 10–7 1 x 10–7 1 x 10–7 3 x 10–14 5 x 10–12
 50 °C (122 °F) 1 x 10–5 3 x 10–6 1 x 10–6 1 x 10–6 2 x 10–12 NA
100 °C (212 °F) 1 x 10–3 1 x 10–4 3 x 10–5 3 x 10–5 1 x 10–9 NA
200 °C (392 °F) 5 x 10–1 1 x 10–2 2 x 10–3 2 x 10–3 2 x 10–6 NA
Kinematic Viscosity ASTM D445 20 °C (68 °F) mm2
/s 60 140 250 310 2560 450
 50 °C (122 °F) (cSt) 15.5 32 52 63 437 NA
100 °C (212 °F) 4.1 7.2 10.6 12.5 64.6 NA
Density 20 °C (68 °F) g/cc 1.88 1.89 1.90 1.90 1.92 NA
 50 °C (122 °F) 1.82 1.83 1.84 1.84 1.87 NA
100 °C (212 °F) 1.73 1.74 1.75 1.75 1.78 NA
200 °C (392 °F) 1.54 1.55 1.56 1.56 1.61 NA
Pour Point ASTM D97 °C (°F) –60 (–76) –54 (–65) –48 (–54) –41 (–42) –15 (5) –35 (–31)
Distillation ASTM D1160 10% °C (°F) 160 (320) 200 (392) 200 (392) 200 (392) NA NA
Range at 0.4 torr 90% 220 (428) 280 (536) 300 (572) 300 (572) NA NA
Heat of Vaporization Knudsen 150–250 °C (302–482 °F) cal/g 9 7 6 6 NA NA
Volatility at 22 hr ASTM D2595 121 °C (250 °F) % 6.5 1.3 0.6 0.4 0.2 NA
Surface Tension 25 °C (77 °F) dyn/cm 17 18 19 19 19 NA
Food Contact Approval NSF H-1/No NSF H-1/No NSF H-1/No None None None
* This table gives typical properties based on historical production performance. DuPont does not make any express or implied warranty that these products will continue to have these 
typical properties.
** Actual values are equal to or less than those indicated.
DuPont™ Krytox® VPF
10-1
10-2
0 20 40 60 80 100 120 140 160 180 200 220 240 260280300 340 380 420
–20 –10 0 10 20 30 40 50 60 70 80 90 100 110120 140 160 180 200 220
10-3
10-4
10-5
10-6
10-7
10-8
10-9
10-10
10-11
10-12
10-13
10-14
Temperature, °F
DuPont™ Krytox® 1525
Krytox® 1514
Krytox® 1506
Krytox® 16256
Krytox® LVP
Temperature, °C
Vapor Pressure (mmHg or torr)
Weight Loss, %
0 10 20 30 40
0 1 5 15
AlCl3
DuPont , wt% ™ Krytox®
PFPE
Type A
PFPE
Type B
Figure 1. Typical Vapor Pressure — Temperature Characteristics Figure 2. Relative Weight Loss of PFPE Fluids in Presence of a Lewis 
Acid (90 min at 120 °C [248 °F] by ISOTGA)DuPont™ Krytox® VPF
Table 3
Krytox® LVP High-Vacuum Grease*
Penetration
(worked, 25 °C [77 °F]), mm/10 280
NLGI Consistency Grade 2
Vapor Pressure
torr at 20 °C (68 °F) <1.0 x 10–13
torr at 200 °C (392 °F) <1.0 x 10–5
kPa at 20 °C (68 °F) <1.3 x 10–14
kPa at 200 °C (392 °F) <1.3 x 10–6
Oil Separation
(30 hr, 204 °C [400 °F]), wt% 13.8
Evaporation Loss
(22 hr, 204 °C [400 °F]), wt% 0.3
Density, (25 °C [77 °F]), g/cc 1.94
*This table gives typical properties based on historical production 
performance. DuPont does not make any express or implied warranty 
that these products will continue to have these typical properties. 
Table 4
Initial Temperature for Depolymerization*
Fluid Type °C (°F)
Perfluoroalky Ether
Krytox® (no -0-CF2
-0- links) 142 (287)
Type A
(some -0-CF2
-0- links) 102 (216)
Type B
(many -0-CF2
-0- links and no shielding) 72 (162)
Hydrocarbon 79 (174)
Silicone 58 (136)
Fluorosilicone 82 (180)
*This is the threshold temperature for the initial reaction in the presence 
of the Lewis Acid Aluminum Chloride as measured in a differential 
scanning calorimeter.