화학공학소재연구정보센터
Journal of Materials Science, Vol.33, No.19, 4687-4696, 1998
Preparation of NbC, TaC and Mo2C fibres and films from polymeric precursors
Polymeric precursors for carbothermal reactions were prepared from niobium alkoxide, tantalum alkoxide and molybdenum ethylene glycolate, respectively, by simultaneous reaction with a chelating reagent (acetylacetone) and organic compounds having two or more reactive OH groups, such as ethylene glycol, saccharose, tartaric acid or dihydroxybenzenes. The precursors exist in common polar and non-polar solvents mostly as linear polymers. The viscous solutions show rheological properties that allow for the preparation of polymer fibres and films. At temperatures up to 1500 degrees C, bulk precursors as well as fibres and films were thermally converted into carbide powders, fibres and coatings. The structural transformations of the polymeric materia Is into carbides were investigated using simultaneous thermogravimetric-differential thermal ana lyses (TGA-DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM).