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ELASTOSIL® A 442

1 of 230 products in this brand
ELASTOSIL® A 442 is a one-component, thixotropic sealant intended for use where a soft, high-elongation material is to be used. It is particularly effective as an adhesive in applications where the bonded joint is subjected to relatively large movements in service.

Product Type: 1K (1 component) Sealant

Application Area: Gaskets

Compatible Substrates & Surfaces: Concrete, Elastomers & Rubbers, Glass, Iron, Metal, Plastics

Cure Method: Moisture Cure

Chemical Family: Silicones

Technical Data Sheet

Knowde Enhanced TDS

Identification & Functionality

Chemical Family

Features & Benefits

Labeling Claims

Applications & Uses

Application Area
Cure Method
Application Details
  • ELASTOSIL® A 442 can be bulk dispensed by hand or robot applicators with conventional drum and pail extruder pumps equipped with high pressure flexible fluid hoses. Caution! Hose pressure rating must exceed the maximum possible output of the pump and be moisture impermeable. 
  • Surfaces to be bonded must be clean and free of oil, grease, soaps, dust, etc. Rubbers and plastics must be free of die lubricants and mold release agents. Certain plastics such as polypropylene require flame treatment to attain maximum adhesion.
  • The surface cure of ELASTOSIL® A 442 may be greatly accelerated by exposure to a moist carbon dioxide rich atmosphere. A carbon dioxide level of one to two percent is sufficient to produce a skin-over time of two to three minutes.
  • ELASTOSIL® A 442 is not recommended for use on polycarbonate or in direct contact with liquid gasoline, diesel fuel or hot engine coolant.

Processing

The performance of ELASTOSIL® A 442 is dependent upon many factors, including the application method, the thickness of the layer deposited, the substrate, the curing atmosphere, and the curing cycle. skin should form over the surface it may be removed by careful skimming. Spray equipment and brushes should be washed and wiped clean with naphtha or mineral spirits after use. The adhesion of ELASTOSIL® A 442 to most substrates can be enhanced by a 30 second to one minute preheat cycle at 60-70°C before exposure to the UV source

Properties

Cured Properties
ValueUnitsTest Method / Conditions
Compression Modulus 100%30psi
Elongation (at break)800%ASTM D 412
Lap Shear Adhesion CRS (1 inch overlap with 0.6 inch bondline, 14 day cure rupture)100psi
Lap Shear Adhesion Movement to Rupture0.4psi
Shore Hardness A18ASTM D 2240
Specific Gravity1.39g/cm³
Tensile Strength225psi
Uncured Properties
ValueUnitsTest Method / Conditions
Extrusion Mass Flow Rate (0.125 inch nozzle at 90 psi)230g/minWSTM-2304
Skin Formating Time (at 23°C, 50% r.h)6minutesWSTM-2118
Tack-Free Time (at 25°C, 50 % r.h)20minutes
Properties
  • Tenacious adhesion to most metals, plastics, synthetic rubbers, glass and concrete
  • Low modulus of elasticity for superior sealant joint movement capability
  • Low compressive modulus, ideal for forming compression gaskets on covers and closures where low clamping pressures are essential
  • Stays flexible between -65°F and 400°F
  • Impervious to weathering and ultraviolet degradation
  • Resistant to hot lubricating oils
  • Causes little or no foam in lubricating oils
  • Non-corrosive to ferrous metals

Regulatory & Compliance

Certifications & Compliance

Packaging & Availability

Regional Availability
  • Africa
  • Latin America
  • North America