Study of Viscosity and Friction of Polyurethane Adhesives

Polyurethane (PUR) adhesives are widely used in various industries for their high performance and versatility. PUR are composed of soft segment (a polyether or polyester polyol) and hard segment (diisocyanate and chain extender). The soft segment provides elasticity, whereas the hard segment increases strength and rigidity through physical cross–linking points. One of the key factors affecting the performance and processing characteristics of PUR adhesives is viscosity during the reaction. Processing parameters like mixing, spreading, and application as well as final properties like gel time, adhesion strength, and tensile strength are all impacted by viscosity during the reaction. The Coefficient of Friction (COF) is also investigated in certain applications such as in automotive and industrial machinery, where the adhesive bond must be able to withstand high loads and maintain its strength.