High Tg Epoxy Systems

Product Enquiry

Newsletter Signup

* indicates required
We respect your privacy and will never share your details with anyone.

When a polymer system such as an epoxy is heated, significant changes occur in mechanical, thermal and electrical properties. These properties do not necessarily recover upon cooling. A considerable change in these properties can be seen above the glass transition temperature (Tg) of the epoxy.  The glass transition is the temperature where the polymer goes from a hard, glass like state to a rubber like state.  The epoxy will exhibit much physical strength and stiffness below the Tg. The Tg is measured by methods such as Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analyzers (DMA) or Differential Thermomechanical Analyzers (DMTA). For many less technical applications, the so called Heat Deflection Temperature (HDT) of the polymer is used in place of the Tg. The Tg of commercial epoxies varies from as low as 50°C to above 200°C.Higher temperature capable epoxy systems require a post cure. This is additional heat that is applied to an epoxy component to help it reach its full physical characteristics. When the epoxy is reacted, and the material starts to plasticize, the ability for the molecules of resin and hardener to find each other and crosslink becomes increasingly difficult. In this case there are partial cross-links formed and in some cases unreacted material. These initial room temperature cures of these epoxy systems give way to a material that is quite brittle, hence termed the ‘B’ Stage. These epoxy systems require additional heat beyond the initial Tg to allow the material to become chemically active again and aid the continuation of the reaction and cross-linking. In order to prevent “overshooting the Tg” when post curing, one should instead  ‘chase’ the Tg, where the part is slowly ramped up to temperature. During this ramp time, as the part approaches and exceeds the initial Tg, additional reaction and cross linking is occurring and the physical properties are being increasingly developed, including the Tg. 

Epolam 2080 epoxy offers very high heat resistance and excellent wetting of the laminate. Epolam 2080 is typically used for composites structures, prepreg moulds, resin transfer moulding...

Max Use Temp:
Tg 190°C

EpoxAcast 670 HT (High Temperature) is an epoxy casting compound which offers high heat resistance up to 177°C if post cured. EpoxAcast 670 HT features...

Max Use Temp:
177°C with post cure