Several factors can contribute to the failure of
an adhesive, including:
- Sunlight
- Heat
- Solvents
- Physical Stresses
- Excessive Loading
Failure of an adhesive often results in fracturing and
eventual separation of the adhesive from the substrate.
Cohesive Fracture
- Cracks propagate into the adhesive, resulting in remnants of adhesive remaining on the substrate.
Interfacial Fracture
- The adhesive separates from the substrate.
Alternating Crack Path
- Cracks jump from one interface to the other.
- Often results from internal stresses in the adhesive.
Fracture in the Substrate/Adherent
- Typically occurs when the adhesive is tougher than the substrate.
- The adhesive remains intact, still bonded to fragments of the substrate.
- Peeling off a paper label is an example of a
fracturing substrate.