Dictionary of Moisture Protection & Restoration

Adhesive failure

Sealant Too Thin

Sealant material applied too thinly results in adhesive failure. When there is insufficient sealant material adjacent to the side of the substrate to permit expansion, the sealant is ripped off the side of the joint (insufficient bonding).

Three-sided adhesion

When the substrate moves, one side will lose its adhesion. This will cause an adhesive failure but could also create a cohesive failure. When performing a pull test on sealant joints, the report will identify the cohesion failure or adhesion failure. The cohesion failure means that the sealant has good adhesion and will break at the center before it will give up the adhesion.

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