Thermal analysis of novel underfill materials with optimum processing characteristics

This work encompasses the development of low‐viscosity cyclic oligomer underfill formulations that cure without heat evolution. Boron nitride, silica‐coated aluminum nitride, and alumina ceramic powders were used as fillers in cyclic butylene terephthalate oligomer melts. The melts were heated with a suitable catalyst to induce polymerization. The effects of the filler type and composition on the thermal and mechanical properties of the poly(butylene terephthalate)/filler composites were examined with differential scanning calorimetry, temperature‐modulated differential scanning calorimetry, thermogravimetric analysis, thermomechanical analysis, and dynamic mechanical analysis. Scanning electron microscopy was employed to elucidate the morphology of these composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1300–1307, 2005