THREE-DIMENSIONAL MICROSCOPIC ASSEMBLIES OF RANDOMLY ORIENTED CARBON ELEMENTARY FILAMENTS AND COMPOSITES CONTAINING SUCH ASSEMBLIES Russian patent published in 1999 - IPC

FIELD: composite materials. SUBSTANCE: assemblies are intended as catalyst carriers, electrodes, chromatographic substances, etc. and also serve as parts of composite structures containing a second material. Assemblies of multiple essentially cylindrical randomly oriented carbon elementary filaments with essentially constant diameter (within a range of 3.5 to 70 nm) and essentially free of pyrolytically deposited carbon exhibit relatively uniform physical properties along one of their dimension axis and have volume density ranging from 0.001 to 0.50 g/cu.cm. In versions, an assembly is presented having relatively isotropic physical properties across at least one of its planes and above-indicated density and another assembly having relatively isotropic physical properties and the same density. Material composition is also presented containing assembly of above-mentioned carbon filaments with volume density 0.001-0.5 g/cu.cm and a composite. The latter includes assembly of the same filaments and a second component made of particles of solid or electrically active material or catalytically active metal or metal-containing compound, in which case assembly has volume density 0.001-0.50 g/cu. cm and contains second component up to 50 parts per 1 part of filaments. Another composite contains assembly with filaments having "c" axes, the same density, and second component: metal or compound in number up to 50 parts per 1 part of filaments. Methods for manufacturing filament assembly and second material involve dispersing filaments or filaments and material and separating resultant assembly, having volume density 0.001-0.50 g/cu. cm, from medium. Method of forming porous mat or sheet (with volume density 0.001-0.50 g/cu.cm) involves dispersing above-mentioned filaments in water or organic solvent to form dispersion with less than 10 wt % of filaments and filtration. One more version of method of manufacturing assembly involves dispersing filaments and separating assembly from medium. In the latter case, filaments have "c" axes passing essentially at an angle less than 90 deg. in respect to their cylindrical axis and assembly has the same density. EFFECT: reduced density of assembly. 22 cl, 1 dwg, 1 tbl, 5 ex