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Technical Data Sheet
Therminol® VP3 Heat Transfer Fluid

  • HTF - fine chemicals
  • Extruding
  • Fibers
  • Polyamide
  • Polyester (pet)
  • Specialty and batch chemical production
  • Specialty chemicals
  • Specialty heat-sensitive polymers
Key Attributes
  • Class III b Combustibility
  • Easy to Handle
  • Low Odor

Product Description

Therminol VP3 heat transfer fluid is a synthetic heat transfer fluid that was specially developed to allow vapor phase heat transfer at lower temperatures than are practical with traditional diphenyl oxide (DPO)/biphenyl constituted fluids like Therminol VP-1.

Performance Benefits

  • Easy to Handle—Therminol VP-3 has a normal boiling point of 243°C (469°F), 14°C (26°F) below the normal boiling point of Therminol VP-1. Laboratory thermal stability testing suggests a recommended continuous operating temperature of 330°C (625°F) in the liquid or vapor phase. A crystallization point of 2°C (36°F) makes Therminol VP-3 easy to handle and may eliminate the need for costly heat tracing in moderate climates.
  • Low Odor—The odor of Therminol VP-3 is milder than other vapor phase organic heat transfer fluids. Therminol VP-3 is a mixture of phenylcyclohexane and bicyclohexyl. It contains virtually no biphenyl.
  • Class III b Combustibility—With an open cup flash point of 104°C (219°F), Therminol VP-3 is a Class III b combustible fluid under the definitions of the U.S. National Fire Protection Association (NFPA) . As with any other combustible material, proper system design and operation are important to safe operation. Leaks of vapor could condense into a stable mist suspension that may be explosive in certain concentrations in air.

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Typical Properties

PropertyTest MethodTypical Value, Units
Appearance Above 2.4°C (36°F) clear, sediment-free liquid
Composition Phenylcyclohexane + bicyclohexyl
Recommended Bulk Temperature 330 °C (625 °F)
Maximum film temperature 360 °C (675 °F)
Normal Boiling Point 243 °C (469 °F)
Crystallization Point 2.4 °C (36 °F)
Flash Point 
     COCASTM D92104 °C (219 °F)
Autoignition TemperatureASTM E659360 °C (680 °F)
 DIN 51794351 °C (664 °F)
Coefficient of thermal expansion 
     @ 200°C 0.001204 /°C (0.000669 /°F)
Viscosity, Kinematic 
     @ 40°CASTM D 4452.04 cSt, mm2/s
Liquid Density 
     @ 15°CASTM D 4052935 kg/m3 (7.8 lb/gal)
     @ 25°CASTM D 4052930 kg/m3 (7.76 lb/gal)
AcidityASTM D 664<0.2 mg KOH/g
Molecular Weight (Average) 161
Pseudocritical temperature 406 °C (764 °F)
Pseudocritical pressure 38.5 bar (558.4 psia)
Pseudocritical density 352 kg/m3 (22 lb/ft3)
Copper CorrosionASTM D 130<<1a
Moisture Content, maximumASTM E-203150 ppm
Surface Tensiona 
     @ 25°C 43.2 dynes/cm
Dielectric Constant 
     @ 23°CASTM D-9242.48

ain air

Properties reported here are typical of average lots. Eastman makes no representation that the material in any particular shipment will conform exactly to the values given.

Eastman and its marketing affiliates shall not be responsible for the use of this information, or of any product, method, or apparatus mentioned, and you must make your own determination of its suitability and completeness for your own use, for the protection of the environment, and for the health and safety of your employees and purchasers of your products. No warranty is made of the merchantability of fitness of any product, and nothing herein waives any of the Seller's conditions of sale.

8/26/2020 5:00:58 AM