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HELISOL® XA is a linear, non-reactive polydimethylsiloxane with a viscosity of approximately 20 mm²/s. Its chemical structure gives it a remarkable set of properties that distinguish it from organic materials like mineral oils. This clear, odorless, and colorless liquid exhibits an outstanding property profile.

Product Type: Heat Transfer Fluid

Features: Anti-Fouling, Good Blocking Resistance, Good Thermal Stability, Heat Resistance, High Durability, High Efficiency, High Linearity, High Reliability, High Temperature Strength, Improved Heat Transfer Efficiency, Long Shelf Life, Low Density, Low Pour Point, Low Viscosity, Non Corrosive, Odorless, Very Good Heat Resistance, Wide Temperature Operating Range

Chemical Family: Silicones

Technical Data Sheet

Knowde Enhanced TDS

Identification & Functionality

Chemical Family
Chemical Structure

HELISOL® XA - Chemical Structure

Features & Benefits

Specific Features
  • Fluid
  • Good heat stability
  • Heat resistant
  • Silicone Fluid
  • Stable upon heating

Applications & Uses

Markets
Applications

Renewable Energies

Application Details
  • Heat transfer fluid in closed systems under inert conditions from -40°C up to 425°C.
  • Recommended use in liquid phase.

Properties

Physical Form
Odor
Odorless, Musty odor
Appearance
Clear colourless liquid
Insoluble in
Water
Typical Properties
ValueUnitsTest Method / Conditions
Boiling Point (at 1013 mbar)393°CEG-Method A.2
Maximum Permitted Film Temperature450°C
Density (at 25°C)0.93 - 0.97g/cm³DIN 51757
Maximum Permitted Working Temperature425°C
Flash Point225°CPensky-Marten
Heat of Combustion24.1kJ/gDIN 51900
Ignition Temperature369°CEN 14522
Kinematic Viscosity (at 25°C)18 - 22 mm²/sDIN 51562
Kinematic Viscosity (at 50°C)approx. 120 mm²/sDIN 51562
pHapprox. 7Specific method
Pour Pointmax. -55°CDIN ISO 3016
Surface Tension19.92mN/m
Thermal Conductivity (at 25°C)0.1451W/m.K
Water Contentmax. 150ppmDIN 51777
Properties
  • High heat resistance
  • Low pourpoint
  • Lower density than water
  • Low viscosity
  • Long life
  • Low fouling potential
  • Non-corrosive
  • No hazard classification

Regulatory & Compliance

Certifications & Compliance

Safety & Health

Safety Notes
  • Reactivity; Chemical stability: Possibility of hazardous reactions No hazardous reactions known if properly stored. When it is used as intended (up to 425 °C), amounts (< 25%) of a mixture of D-cyclic siloxanes (including octamethylcyclotetrasiloxane (D4, CAS 556-67-2) and decamethylcyclopentasiloxane (D5, CAS 541-02-6)) are formed. This depresses the flash point and increases the vapor pressure.
  • Conditions to avoid: Permeation of oxygen and water or any contamination at operating temperature.
  • Incompatible materials: None known.
  • Hazardous decomposition products : When it is used as intended (up to 425 °C), it has been found that in the absence of oxygen and after relatively long operating times, extremely small quantities of methane, hydrogen and volatile silanes (tetramethylsilane, CAS 75-76-3 and trimethylsilane, CAS 993-07-7) may be produced, which further depress the flash point.

Packaging & Availability

Country Availability
Regional Availability
  • Africa
  • Asia
  • Europe
  • Latin America
  • Middle East
  • North America
  • Oceania
Packaging Information
  • 0.5 kg bottle
  • 5 kg can
  • 25 kg drum
  • 200 kg drum
  • 950 kg IBC

Storage & Handling

Storage Information

Maximum temperature allowed during storage and transportation: 50°C.