ELASTOSIL® 4500 is a one-component, acid-curing silicone sealant for general-purpose sealing in high temperature applications up to 250 °C.
ELASTOSIL® 4500 cures at room temperature in the presence of atmospheric moisture to give a permanently flexible silicone rubber.
- ready gunnability at low (+5 °C) and high (+40 °C) temperatures
- flexible at low (-40 °C) and high temperatures (+250 °C)
- acetic acid crosslinking system
- rapid crosslinking: quickly becomes tack-free
- adheres excellently to glass, vitrified surfaces, ceramic tiles, non corrosive metals and many coatings
- good tooling properties
- maintains elastic properties at continuous temperatures of up to 250 °C
- short-term resistance up to 275 °C
- Sealing of connecting and expansion joints exposed to high temperatures
- Sealing of joints exposed to long-term temperatures of 250 °C (oven and chimney construction)
- Suitable for industrial applications
The substrate areas that will be in contact with the sealant must be clean, dry and free of all loose material such as dust, dirt, rust, oil and other contaminants. Non-porous substrates should be cleaned with a solvent and a clean, lint-free, cotton cloth. Remove residual solvent before it evaporates with a fresh clean, dry cloth.
ELASTOSIL® 4500 exhibits excellent primerless adhesion to most non-porous siliceous material, e.g. glass, tiles, ceramics, enamel, glazed tiles, clinker and non corrosice metals.
Users must carry out their own tests due to the great variety of substances. The adhesion can be improved in many cases by pretreatment of the substrates with a primer. If adhesion difficulties arise please contact our technical service.
ELASTOSIL® 4500 is heat stabilized and remains unaffected by long term exposure to extreme temperatures up to 250 °C. It can also be used for shorter periods (some weeks) at temperatures up to 275 °C.
Figure 2 shows the effect of heat aging at 275 °C on the elongation at break, tensile strength and hardness of the silicone rubber.
Restrictions on use
ELASTOSIL® 4500 should not be used on substrates such as concrete, fibrous cement and mortar, as the product releases acetic acid during vulcanization.
ELASTOSIL® 4500 should not be used in contact with metals such as lead, copper, brass or zinc due to corrosion.
ELASTOSIL® 4500 may be discolored in contact with some organic elastomers, e.g. EPDM, APTK and neoprene.
ELASTOSIL® 4500 is not recommended for sealing of aquaria, please use our ELASTOSIL® 4300.
ELASTOSIL® 4500 is not recommended for use on natural stone, such as marble, granite, quartzite, as it can cause staining.
ELASTOSIL® 4500 is not recommended for structural glazing bonding.
ELASTOSIL® 4500 is not suitable as a cylinder head gasket or for parts that are constantly exposed to fuels (petrol).