Showing papers by "Florence Babonneau published in 1991"

Synthesis and characterization of SiZrCO ceramics from polymer precursors

Abstract: Polyzirconocarbosilane has been prepared from polycarbosilane and zirconium alkoxide. The structure of this Zr-modified polymer as well as its conversion process into SiC/ZrC crystalline material has been investigated, using mainly MAS-NMR and XRD techniques. This work is part of a more comprehensive study on the pyrolysis process of polycarbosilanes modified with metallic alkoxide M(OR) n (M = Ti, Zr, Al). The crystallization behavior has been compared with results already found for SiTiCO and SiAlCO systems and will be discussed.

Synthesis and Characterization of β’-SiAlON Ceramics from Organosilicon Polymers

Abstract: A polycarbosilane has been modified with aluminum alkoxide to obtain a new preceramic compound. The pyrolysis in NH3 flow of this polyaluminocarbosilane leads to the formation of an amorphous Si-Al-O-N phase. The nitridation process has been followed by IR and 29Si MAS-NMR spectroscopies. A fine-grained β-SiAION ceramic is obtained by firing the amorphous phase at 1500°C. The crystallization process has been studied by XRD, 29Si MAS-NMR, and TEM techniques.