How does Liquid Glue affect the bonding of different materials?

Liquid Glue plays a key role in the bonding of different materials, and its effect on the bonding effect varies from material to material.
For porous materials, such as wood and paper, liquid glue can penetrate into the pores of the material to form a mechanical anchoring effect, thereby improving the bonding strength. However, attention should be paid to the viscosity of the glue. If the viscosity is too low, the glue may over-penetrate, resulting in a lack of glue on the surface, affecting the bonding effect; if the viscosity is too high, it may not fully penetrate, which will also reduce the bonding strength.
When bonding materials with smooth surfaces, such as glass and metal, liquid glue mainly relies on the intermolecular force to achieve bonding. At this time, the wettability of the glue is very important. It needs to be able to fully wet the surface of the material to increase the contact area between the glue and the material. If there are contaminants such as oil, dust, etc. on the surface of the material, it will affect the wettability of the glue, resulting in poor bonding effect, so the surface needs to be cleaned before bonding.
For elastic materials, such as rubber and plastic, liquid glue needs to have a certain degree of flexibility and elasticity to adapt to the expansion and deformation of the material. If the glue is too hard and brittle, the bonding part is prone to cracking when the material is stretched or bent by external force, resulting in bonding failure.
Different liquid glue ingredients also affect the bonding effect. For example, water-based glue is environmentally friendly, but the bonding effect on some hydrophobic materials may not be as good as solvent-based glue; hot melt adhesive has the characteristics of fast curing and high bonding strength, but has strict requirements on operating temperature and time.
Environmental factors can also affect the bonding effect through liquid glue. Too low temperature will slow down the curing speed of glue or even make it impossible to cure; too high humidity may dilute the glue or affect its chemical reaction, reducing the bonding strength.