Syntheses and characterizations of thermally reworkable epoxy resins. Part I

To meet the need for reworkable epoxy resins, a series of cycloaliphatic diepoxides containing thermally cleavable carbamate linkages were synthesized and characterized. These materials were shown to undergo curing reactions with cyclic anhydride in a similar fashion as a commercial cycloaliphatic epoxide, except that the carbamate group within the diepoxides can act as the internal catalyst. Furthermore, cured samples of the formulations from these diepoxides started to decompose at lower temperatures, i.e., between 200–300°C as compared with 350°C for the cured sample of the commercial cycloaliphatic epoxide, which showed their potential to be used as reworkable underfill encapsulants in the electronic packaging area.