Sticking to Silicone & Bonding with a ‘Low Surface Energy’ Material Adhesives

silicone-based adhesivesIt’s normally not that hard to stick different material together, but when sticking silicone extrusions to different substrates, the only thing that can stick to silicone is almost always silicone.

This is where we often find non-silicone based adhesives fail. They generally lack this property unique to silicone and when failure occurs it can lead in-field leakage, warranty claims and not so happy customers.

We often get asked exactly why Silicone materials are resistant to glues and adhesives. It comes down to the fact of it having a ‘Low Surface Energy” in contrast to other materials.

This means that in short those molecules on a surface of Silicone say compared to standard wood glue are energetically less favourable than other materials. This means Silicone is quite resistant in its own right, making it a great sealing material for a range of applications.

The best adhesives to glue silicone to metal or plastic substrates are silicone-based adhesives. Silicone adhesive works by providing a strong, flexible bond between silicone parts along with high elongation.

Silicone rarely fails in application and in the instances it does, it’s quite often due to contamination of the adhesive. So before installing the silicone seals, it’s necessary to clean the application substrates with clean fabric and detergent.

A variety of detergents could achieve this including detergent with isopropyl alcohol. Use of detergents with lotions, waxes, fragrances, oils or creams is not advisable as then can often leave an invisible residue on the surface.

For example interior grove walls with grease and/or oil present will need special attention for removal of contaminants. Quite often this will require cleaning with a solution of isopropyl alcohol with warm water and a ‘lint-free’ cloth.

Usage of primers is also another way of adding strength to the adhesion. By priming the surface of a silicone rubber, one can enhance the bond ability potential by changing the surface chemistry. Combined with certain adhesives the user of primers can be very effective.

For more information about Jehbco’s silicone rubber and its silicone-based adhesives that only stick to it, Contact Us right here