The Higher The Viscosity of The Glue, The Higher The Bonding Strength?

Many people tend to fall into a misunderstanding: equating "adhesive viscosity" with "bonding strength" and confusing them. In fact, the reason for the mistake is that the glue parameters are not clear enough. Today, let me introduce you to the viscosity and bonding strength of adhesives, hoping to help you have a deeper understanding of adhesive parameters and avoid detours when using them!

Adhesive viscosity

Viscosity is an important parameter of adhesives. It reflects the strength of the interaction between liquid molecules during movement and is a physical data used to measure the magnitude of viscous force. The relative movement of adjacent fluid layers when the fluid flows, and the friction resistance between the two fluid layers is called viscous resistance.

Simply put, in adhesives, viscosity is a reference value that reflects whether the adhesive is thin or thick. Usually, the thicker the glue, the slower the flow and the greater the adhesive force; conversely, the thinner the glue, the faster the flow, and correspondingly, the smaller the viscosity of the adhesive.

Bonding strength

The bonding strength of adhesives is one of the important indicators for evaluating the quality of adhesives. Bonding strength refers to the stress required to cause the interface between the adhesive and the adherend or its vicinity in the adhesive under the action of external force to be destroyed. In addition, according to the stress conditions during the use of the adhesive, the bonding strength is usually subdivided into shear strength, tensile strength, peel strength and impact strength.

The magnitude of bonding strength depends not only on the bonding force, the mechanical properties of the adhesive, the properties of the adherend, and the bonding process, but also on the joint form, stress conditions (type, size, direction, frequency), environmental factors (temperature, humidity, pressure, medium) and test conditions, experimental technology, etc.

It is worth noting that bonding force is only one of the important factors that determine bonding strength. It is a completely different concept from bonding strength and cannot be equated.

Summary

The above is an introduction to adhesive viscosity and bonding strength.

There is a big difference between the two in essence.

So don't think that the higher the viscosity of the adhesive, the higher its bonding strength.

Because the bonding strength does not have a fixed value in theory.

It must be combined with the material of the adherend to make sense.

It must be noted that the actual bonding strength of adherends of different materials is very different!