Many different starting materials are available in the formulation of two-part adhesives, all of which will require a variety of mixing, dispensing, and application methods.
Two-part adhesives are an ever-growing segment of the adhesive and sealant industry, with applications in aerospace, construction, automotive, consumer goods, and the DIY/repair sectors. With the U.S. accounting for roughly one-third of the adhesives used worldwide, demand for cost-effective, efficient products that meet the desired criteria—formulating, mixing, metering, and dispensing—are all critical components that must be identified and optimized to ensure that quality and quantity demands are met.
Many different starting materials are available in the formulation of two-part adhesives, all of which will require a variety of mixing, dispensing and application methods. A discussion of such breadth and depth is covered in the wide assortment of texts,1 with this article focusing primarily on two-part (2K) polyurethane (PUR) reactive adhesives, which cure at room temperature, and the mixing conditions to consider when selecting equipment. Table 1 provides a brief summary of various properties that should be considered throughout the numerous steps in the manufacture of a 2K PUR system.