Novel foaming methods to fabricate activated carbon reinforced microcellular phenolic foams

Polymer foams are used for thermal insulation and weight reduction in multiple fields, such as buildings, automobiles, and LNG containment systems. Phenolic foams are preferred as a thermal insulator due to a lower flammability and lower gas generation than other polymeric insulation foams. For conventional foaming methods, the extensive time to fabricate large volumes and environmental regulations limit the use of blowing agents. In this study, new foaming methods for an activated carbon (AC) reinforced microcellular phenolic foam were developed using microwaves instead of the blowing agents. Both thermal and mechanical properties were measured to characterize the foaming conditions, including the aging time of the resin before microwave foaming and the weight percent of the AC. We found that the microcellular phenolic foams fabricated under these optimum foaming conditions had low thermal conductivities and low densities that are suitable for insulating foams.