Patent ID: 6103149
Filing Date: 2000-08-15
Classification: C04B

Abstract:
A method for producing reticulated carbon foam with a controlled aspect ratio between 0.6 to 1.2 including the following steps,providing an open cell polyurethane foam,providing a catalytically curable carbonaceous thermal setting resin,impregnating the foam with the resin,curing the impregnated foam under a controlled curing cycle in an inert or reducing atmosphere or a vacuum, wherein the controlled curing cycle includes a specific exotherm plateau temperature where the curing cycle is substantially isothermally maintained for sufficient time to allow the first exothermic reaction of the thermal setting resin to release heat sufficient to soften the polyurethane foam ligaments, and allow the resultant softened polyurethane foam ligaments to assume the required shape under the weight of at least said impregnated foam to produce the desired aspect ratio and to begin crosslinking, and wherein the resulting shaped, partially crosslinked, impregnated foam continues on the controlled curing cycle along a controlled heat-up ramp, while substantially maintaining said required shape until the resin is at least substantially crosslinked, andpyrolyzing the resulting crosslinked foam in an inert or reducing atmosphere or vacuum until the crosslinked resin is transformed into vitreous carbon foam with cells having the shape and aspect ratio between 0.6 to 1.2 created during the specific exotherm plateau provided during the controlled curing cycle.