Many formulation factors influence the performance properties of UV curing pressure sensitive adhesives (PSAs). This article is meant to serve as a primer for formulating these useful adhesives that are found everywhere.
There are several basic material fundamentals that need to be taken into account regarding the formulation of UV curing PSAs. These include polymer rheology, molecular weight, functionality, and crosslink density. These topics will be addressed first to provide insight into the behavior of polymeric materials in PSA applications. The various raw materials that are used in practical UV formulations will then be reviewed as well as formulations for certain applications.
Whereas, the vast majority of the commercially available UV curing PSA systems is based on free radical curing liquid systems, emphasis will be on this technology. If interested in cationic cure UV/EB systems, the reader is referred to a previous SpecialChem article. UV curable hot melt PSAs have also been discussed in several previous articles.