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HELISOL® 5A is a linear, non-reactive polydimethylsiloxane with a viscosity of approximately 5 mm²/s. Its unique chemical structure gives it exceptional properties that differentiate it from organic materials like mineral oils. HELISOL® 5A is a clear, odorless, and colorless liquid.

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

Knowde Enhanced TDS

Identification & Functionality

Chemical Family
Chemical Structure

HELISOL® 5A - 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 Point215°CEG-Methode A.2
Maximum Permitted Film Temperature450°C
Density (at 25.0°C)approx. 0.92 g/cm³
Maximum Permitted Working Temperature425°C
Flash Point120°CPensky-Marten
Heat of Combustion26.3MJ/kgDIN 51900
Ignition Temperature358°CEN 14522
Kinematic Viscosity (at 25°C)4 - 6 mm²/sDIN 51562
pHapprox. 7
Pour Pointmax. -55°CDIN ISO 3016
Water Contentmax. 150ppmDIN 51777
Properties
  • High heat resistance
  • Low pourpoint
  • Lower density than water
  • Long life
  • Low fouling potential
  • Non-corrosive
  • No hazard classification

Regulatory & 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
  • 0.4 kg bottle
  • 5 kg can
  • 25 kg drum
  • 180 kg drum
  • 900 kg IBC

Storage & Handling

Storage Information

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