High temperature carbonaceous cement

Abstract

A curable, high temperature, carbonaceous, cement paste composition comprising a catalyst; a carbon filler present in an amount of about 20 to about 60 wt. %; a polymerizable monomeric system present in an amount of about 7 to about 30 wt. % comprising a dialkyl ester of an aromatic tetracarboxylic acid, an aromatic diamine, and a monoalkyl ester of an acid selected from the group consisting of 5-norbornene-2,3-dicarboxylic acid and phthalic acid; and a furan solvent present in an amount of about 20 to about 60 wt. %. The most preferred embodiment comprising a monomeric system comprising a dimethyl ester of 3,3′,4,4′-benzophenonetetracarboxylic acid, 2,2′-bis (4-[4-aminophenoxyl]phenyl)propane and a monomethyl ester of 5-norbornene-2,3-dicarboxylic acid with furfuryl alcohol and a catalytic solution of about 50% ZnCl,, has a glass transition temperature of about 280° C. after curing by heating at about 2° C./minute to about 240° C. and holding for about 2 hours. Upon curing, the cement paste composition maintains a strength of at least about 2000 psi at room temperature after heat treatment at about 3000° C. even when cured at a substantially lower temperature of at least about 200° C. Subsequent heating of the monomeric binder causes further cross-linking producing a stronger and more stable cement for use at service temperatures greater than the initial glass transition temperature of the cured cement. The curable cement composition may be used along with a pre-coat in an adhesive system for attaching together carbon bodies. Most preferably, the pre-coat comprises about 27 wt. %, of a monomeric system comprising a dimethyl ester of 3,3′,4,4′-benzophenonetetracarboxylic acid, 2,2′-bis (4-[4-aminophenoxyl]phenyl)propane and a monomethyl ester of 5-norbornene-2,3-dicarboxylic acid dissolved in about 65 to about 85 wt. % furfuryl alcohol. A method of making the cement paste composition is also described.