METHODS FOR MAKING A PITCH-BASED CARBON FOAM

A mesophase pitch material having a melting point in excess of 350 DEG C has a solvent added thereto to provide a solvated mesophase pitch. A low molecular weight solvent is used so that the melting point can be brought low enough to create a carbon foam at a convenient temperature. The solvent is then removed by heat and/or vacuum and, consequently, the pitch reverts to a high melting point of approximately greater than 350 DEG C. The pitch can then be heated or carbonized without an oxidative stabilization step. Alternatively, a solvated mesophase pitch material may be used initially for foaming. A mesophase pitch material having a melting point in excess of 350 DEG C has a solvent added thereto to provide a solvated mesophase pitch. A low molecular weight solvent is used so that the melting point can be brought low enough to create a carbon foam at a convenient temperature. The solvent is then removed by heat and/or vacuum and, consequently, the pitch reverts to a high melting point of approximately greater than 350 DEG C. The pitch can then be heated or carbonized without an oxidative stabilization step. Alternatively, a solvated mesophase pitch material may be used initially for foaming. Un matériau de brai à mésophase ayant un point de fusion dépassant 350 DEG C est additionné d'un solvant afin d'obtenir un brai à mésophase solvaté. On utilise un solvant de faible masse moléculaire de manière à permettre d'abaisser le point de fusion suffisamment pour créer une mousse de carbone à une température convenable. Le solvant est ensuite extrait sous l'effet de la chaleur et/ou d'un vide et, ensuite, le brai revient à un point de fusion élevé approximativement supérieur à 350 DEG C. On peut ensuite chauffer le brai ou le carboniser sans étape de stabilisation oxydante. On peut aussi utiliser initialement pour le moussage un matériau de brai à mésophase solvaté.