有机助剂和老化温度对氧化锆纤维前驱体溶胶稳定性的影响

Influences of organic modifier and aging temperature on stability of precursor sol for zirconia fiber

采用溶胶-凝胶法制备多晶氧化锆纤维,以氧氯化锆为主要原料,硝酸钇为相稳定剂,醋酸和柠檬酸为有机助剂合成氧化锆纤维前驱体溶胶。通过对溶胶黏度的测定,研究了不同条件下溶胶的凝胶化过程,探讨了溶胶-凝胶化转变过程中老化温度和有机助剂对体系凝胶化时间的影响。结果表明：当柠檬酸与氧氯化锆物质的量比在0.30~0.40时,胶体的稳定性较好;醋酸的加入延缓了凝胶化进程;随着老化温度的升高,胶体的凝胶化时间缩短。

Polycrystalline zirconia fibers were synthesized with sol-gel method.The precursor sol was prepared using zirconium oxychloride octahydrate as starting material,yttrium nitride as phase stabilizer,acetic acid and citric acid as organic modifier.The sol-gel transition of zircoina fiber precursor sol under different conditions was investigated through viscosity measurement.The influences of modifier and aging temperature on gelation time of the precursor sol in the process of sol-gel transition were also studied.The results indicate that when the molar ratio of citric acid and zirconium oxychloride octahydrate is 0.30-0.40,the system has good stability;the addition of acetic acid delays the gelation process;as the aging temperature increases,the gelation time decreases.