Preparation and Characterization of Zirconium-containing Ceramic Precursor Used for Impregnation

A kind of low cost and toxicity ceramic precursor with zirconium (PZC) used for impregnation was successfully synthesized with phenol, paraformaldehyde (PA), ZrOCl2 center dot 8H(2)O, acetylacetone (Hacac) and H2O2 as raw materials. The precursor was air stable and can be diluted in ethanol to any expected viscosity. The composition, structure, viscosity and pyrolysis process of the precursor were analyzed by X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR),Fourier transform infrared spectra (FTIR), the cone and plate rheometer and thermogravimetric analyser-differential scanning calorimetry (TG-DSC). The results showed that incorporation of Zr- on to the polymer backbone was successfully done, using Hacac as complexing agent and ethanol as solvent, and the obtained precursor might be Zr-O and Zr-O-C chain polymer with acetylacetone and hydroxymethyl phenol as ligands. During reaction, the coordination compound [Zr] prepared by the coordination reaction between ZrOCl2 center dot 8H(2)O and acetylacetone (Hacac) was the main reactive group. And PZC was prepared by the coordination reaction of [Zr] and the hydroxymethyl phenol which was synthesized by reaction between phenol and formaldehyde. Results indicated that the precursor showed long temperature range of 40 similar to 80 degrees C and low viscosity of 50 similar to 800 mPa.s,which was suitable for impregnation. The ceramic yield ratio of the precursor was 48% at 1400 degrees C, pyrolysis products were ZrO, and ZrC,while initial formation temperature of ZrC was higher than 1200 degrees C, and the precursor transformed into ZrC completely at 2000 degrees C. Thus, it is a kind of ceramic precursor suitable for infiltration and pyrolysis to obtain ZrC modified carbon/carbon composites.