Most of the hot melt adhesive materials are solid and have no stickiness at room temperature. Why does the hot melt adhesive become sticky after heating?
According to current information and previous studies. There are roughly two theories: one view is that the viscosity is essentially determined by the physical properties of the two systems of adhesives; the other view is that the viscosity is determined by the viscoelastic deformation characteristics. At present, there are more people who support the latter view. Because the theory of viscoelasticity can explain more experimental facts.
Viscoelasticity is a research branch of solid mechanics, also known as rheology. It is based on the elastic properties and viscous properties of materials to study the distribution of internal stress and strain of materials and the relationship between them and external forces. The viscous nature of the material is mainly related to the stress and strain rate in the material, and the viscoelastic body can be understood as a mixture of elastomer and liquid.