ISO-PUR® BD50-FL
• low viscosity
• good low-temperature performance
• flame retardant acc. to UL94 V-0
ISO-PUR® BD50 FL is a cold-curing, two-component polyurethane casting resin based on liquid rubber and polymeric aromatic diisocyanates. Due to its very high hydrophobicity, the compound is ideally suited for moisture protection in telecommunications and for sealing many other electronic components. Further applications include potting antennas and sensors (control boards) in various fields (for example, in the automotive industry). The casting compound has passed flame retardancy tests according to UL94 V-0 (13 mm) and is therefore particularly suitable for casting electrical components tested according to UL standards. Even at low temperatures (Tg < -60°C), the product exerts practically no mechanical stress on sensitive electronic components and reliably protects these parts against environmental influences. The material exhibits excellent hydrolysis stability. The cured material does not contain any phthalates and does not tend to become brittle. Compared to standard polybutadiene casting resins, the material exhibits high temperature stability due to the use of special additives to protect against thermo-oxidative degradation. The cured product adheres well to metal, ceramics, and many plastics. ISO-PUR® BD50-FL is compliant according to EU Directives 2011/65/EU (“RoHS”) and 2015/863/EU (“RoHS III”).
Technical data
Resin
Colour
Viscosity (25°C; rot.; 1 s-1)
Viscosity (25°C; rot.; 10 s-1)
Density (23°C)
Black (other colours on request)
Approx. 2800 mPas
Approx. 1600 mPas
Approx. 1,33 g/cm³
Hardener
Colour
Viscosity (25°C; rot.; 1 s-1)
Viscosity (25°C; rot.; 10 s-1)
Density (23°C)
Brown
Approx. 130 mPas
Approx. 120 mPas
Approx. 1,23 g/cm³
Mixture
Mixing ratio resin : hardener
Colour
9,1 : 1 parts by weight
Black (other colours on request)
Density (23oC)
Approx. 1,32 g/cm³
Pot life (23°C)
Gel time (23°C)
Approx. 10 min
Approx. 40 min
Mixed viscosity (25°C; rot.; 1 s-1)
Mixed viscosity (25°C; rot.; 10 s-1)
Approx. 4100 mPas
Approx. 1800 mPas
Dielectric strength
> 7 kV/mm
Cured product
Mixing ratio resin : Hardener
Under standard curing condition
9,1 : 1 parts by weight
(14 days 23°C / 50% rel. h.) if not stated otherwise
Hardness Shore 00
(23°C; 14d RT 50% rel. h.)
Hardness Shore 00
(23°C; oven curing: 4hRT + 24h80°C)
Approx. 88
> 90
Hardness Shore A
(23°C; 14d RT 50% rel. h.)
Hardness Shore A
(23°C; oven curing: 4hRT + 24h80°C)
Approx. 44
Approx. 66
Long-term temperature resistance
Short-term temperature resistance
Approx. 120°C
Approx. 140°C
Flame retardancy test according to UL94
V-0 (13 mm)
Glass transition temperature (midset)
< -60°C
Tensile strength (5A specimen)
(2 mm thickness; speed: 10 mm/min; 23°C)
Elongation at break (5A specimen)
(2 mm thickness; speed: 10 mm/min; 23°C)
Approx. 1,10 N/mm2
Approx. 200%
Tear resistance
(W-specimen; incision; speed: 10 mm/min; 23°C)
Approx. 2,55 N/mm
Dielectric strength
> 20 kV/mm
Dielectric loss factor tan δ (25°C; 500 V AC; 50 Hz)
Approx. 0,06
Relative permittivity (25°C; 500 V AC; 50 Hz)
Approx. 5,30
Insulation resistance (25°C; 500 V DC)
Approx. 4,60×1010 Ohm
Volume resistance (25°C; 500 V DC)
Approx. 6,40×1012 Ohm×cm
Surface resistance (25°C; 500 V DC)
Approx. 5,50×1011 Ohm×cm
Water absorption
After 28 days in water (immersion, 23°C)
Approx. 1,60%
Water vapour permeability
(75% rel.h.; 23°C; 1 mm thickness)
Approx. 2,60×10-6 g/(day×mm2)
Storage and transport
Store in a dry and airtight, closed container at 10 – 35°C. Can be stored for at least 12 months in original sealed containers under the above conditions. Short-term deviations during transport and storage are acceptable.
Cleaning
To ensure good adhesion of the cast resin the customer should individually test the suitability of the involved surfaces. Possible pre-treatments like cleaning, activation processes (plasma pro-cess) etc. should also be taken into account. The contact surfaces should be free of dirt such as dust, grease or water. For cleaning we recommend ISO-RC® Degreaser for wipe degreasing or ISO-RC® Flux-Off + ISO-RC® Spraywash for spray degreasing (available in 400 ml spray cans).
Processing
Stir up the resin container thoroughly before use to remove any possible sedimentation. Weigh the resin and hardener in the desired mixing ratio and mix for 1 – 3 minutes (depending on mixed quantity and processing time). Apply suitable mixing speed in order to ensure complete homogeneous mixing without introducing too many air bubbles into the reaction mass. The ideal processing temperature is 20 – 25°C. In general, curing is delayed at lower temperatures and accelerated at higher temperatures. When using a double chamber bag, empty the corners well and knead for 3 minutes. Before casting, a homogeneous mass, free of streaks, must be obtained. Then pour immediately and do not scrape the mixing vessel. Air bubbles in the reaction mass can be removed before the end of the potlife by evacuating the material or carefully fanning the surface with a hot air gun. Machine casting is also possible.
The EC safety data sheet provides information on safety-relevant product properties.
Hardener component (containing diisocyanate): As of August 24, 2023, appropriate training must be provided before industrial or commercial use.