APPLICATION OF FLOW MICROCALORIMETRY TO DEVELOP UNDERFILL RESINS

摘要

A series of model underfill resins with different chemical structures have been characterized using flow microcalorimetry (FMC). FMC allows the direct observation of the strength of adsorption of molecules onto a surface. In this case, epoxy monomers, curing agents, and adhesion promoters, were adsorbed onto a borosilicate glass powder in an effort to predict adhesive strength. Adhesives strengths were measured mechanically using an asymmetric double cantilever beam test. Adhesive strengths of filled and unfilled epoxies resins were measured and often correlated to FMC results. Scanning electron and optical microscopy were used to identify mechanisms of plasticity/damage at interfacial crack tips. Greater adhesion strength can be attributed to increased damage near the crack tips. Such damage is enabled by strong molecular interactions at the interface.