Glue knowledge

What are the key properties of a good sealant?


Several key properties of flexibility:

Weather:

Under severe weather conditions by tensile and compression can maintain its effectiveness without cracking or "cracking" characteristics, that is, the gradual change in the chemical and physical properties of sealant; Such as solvent evaporation, immersion, plastic infiltration, ultraviolet and ozone erosion, etc. directly affect the weatherability of sealant.

Tensile strain:

Sealant as the temperature decreases, the base material shrinks, so that the joint shrinkage performance.

Tensile strength:

The resistance of sealant to tensile force when pulling the specimen; It is measured in units of Mpa.

Elongation:

Percentage increase relative to the original sample length. (The elongation has little or no relation to the amount of elongation that the sealant can withstand under actual conditions).

Modulus of elasticity:

The tensile ratio of the sealant to a certain point. Sealant with high modulus of elasticity, the bonding layer/adhesive layer has a high stress, such stress can destroy the joint displacement capacity. Low modulus of elasticity sealant can provide higher displacement capacity.

Displacement capacity:

The +/- percentage value indicates the amount of tension and/or compression the sealant can withstand relative to the original joint width. A sealant with a high displacement capacity reduces the joint or calculated joint gap.

Response rates:

The proportion of the sealant returning to its original shape after stretching or compression.

Stress release:

The opposite of reply. The stress decreases after the continuous strain (elongation) condition, and the stress decreases at the bonding layer.

What are the key indicators of adhesiveness

Adhesiveness has two key properties:

Bonding strength:

Measure the adhesive ability of sealant to the base material. It's measured in units of Mpa.

Tear resistance:

Resistance of joints to mechanical damage (chain effect).