Two-parts silicone adhesives

Two-part silicone adhesives start to cross-link (or cure) as soon as the two components are mixed. Their main attractive feature is their cure time which increases productivity and makes them compatible with bonding large thicknesses.

Two-part silicone adhesive is available in a number of formulations which cure in different ways to form a rubbery elastomer:

• At ambient humidity; products known as RTV (Room Temperature Vulcanisation) adhesives
• At high temperatures; these products are referred to as HTV (High Temperature Vulcanisation) adhesives

Two-part RTV silicone adhesives cross-link (or vulcanise) by polycondensation at room temperature (as a result of absorbing moisture from the ambient air).

At normal temperatures and humidity levels (25°C and 50% RH), silicone adhesive cures slowly (3 mm of depth/24 h) however, the cross-linking process can be accelerated by increasing the humidity level and/or the temperature.

Two-part HTV silicone adhesives cross-link by polyaddition when exposed to high temperature (approximately 150°C). Unlike RTV adhesives, these adhesives do not require moisture in the ambient air to cross-link, and for this reason they can be used in places where the availability of air is limited. This type of adhesive cures very quickly.

The various ranges of two-part silicone adhesives produced by ADDEV Materials are available in a wide range of viscosities to suit their intended application.