HOW MANY KINDS OF EPOXY ADHESIVE ARE THERE?

Epoxy adhesives are classified into 2 groups:

• 2-component epoxy adhesive (Epoxy 2C)
• 1-component Epoxy Adhesives (Epoxy 1C)

1. 2-COMPONENT EPOXY ADHESIVES

Basic components of adhesive epoxy 2C:

• Resin - diepoxide or polyepoxide - Component A
• Hardener - Polyamines or mercaptans - Component B

Curing time varies from few hours to several days. Due that it is a 2-component adhesive, after mixing , it begins to occur curing chemical reactions, the pot-life varies with the temperature of use, an increase in temperature acts as an accelerator of chemical crosslinking reaction by reducing the pot life of the adhesive.

It is very sensitive to the mixing errors; it usually that this kind of adhesive or glue, comes in a cartridge with the two components, which are mixed in proper proportion in order to avoid mistakes.

TYPICAL PROPERTIES OF EPOXY 2-COMPONENTS:

Mechanical properties:

• High resistance to stress or loads over 30 Mpa
• Low elongation to fracture, 10%

Chemical properties:

• High resistance to chemical and physical agents.
• High resistance to temperature.
• Tendency to absorb moisture.
• Good adhesion to aluminum, steel and many plastics

2. 1-COMPONENT EPOXY ADHESIVES

Basic components of adhesive epoxy 1C:

• Resin - diepoxide or polyepoxide.
• Hardener - Polyamines, mercaptans, phenolic resins...

1-component epoxy adhesive requires heat input in order to activate the hardener, starting the process of crosslinking and curing.

Some epoxy adhesives 1 component has the ability to absorb oils, not being needed cleaning pretreatment of oils.

TYPICAL PROPERTIES OF EPOXY 1-COMPONENTS:

Mechanical properties

• High resistance to stress or loads, about 35 or 40 MPa, higher than the epoxy adhesive of 2-components.
• Low elongation to fracture

Chemical properties

• Good resistance to chemical and physical effects
• High resistance to temperature.
• Tendency to absorb moisture
• They can absorb oil