화학공학소재연구정보센터
Journal of Materials Science, Vol.33, No.19, 4697-4706, 1998
Synthesis of polymeric titanium and zirconium precursors and preparation of carbide fibres and films
Polymeric precursors for carbothermal reactions were prepared from the chelate derivatives of titanium and zirconium alkoxides L2M(OR)(2) (L is an acetylacetonato or ethyl acetoacetato group) in alcohols by reaction with organic compounds having two or more reactive OH groups, such as ethylene glycol, saccharose, tartaric acid or dihydroxybenzenes. These organic groups act as bridging ligands in transesterification and condensation polymerization yielding either spinnable viscous solutions or elastic gels. The rheological properties of the concentrated solutions allowed for the preparation of polymer fibres and films. At temperatures up to 1600 degrees C, bulk precursors as well as fibres and films were thermally converted into carbide powders, films or coatings. The structural transformations of the polymeric materials into the carbides were investigated using thermogravimetric-differentia I thermal ana lyses (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FTIR) analysis and Raman spectroscopy.