非硅氧化物的滤出及其机理探讨

 采用B核磁共振仪,激光拉曼光谱仪,隧道扫描显微镜及各种化学分析等方法,较系统地研究了沥滤温度、时间和酸液浓度对拉制的钠硼硅玻璃纤维纯度的影响。结果表明,高钝超细SiO_2,纤维可以用酸沥滤法获得;揭示了纤维中非硅氧化物沥出的规律;并初步探讨了沥滤机理,认为沥滤过程主要是B~(3+)和N~+与H~+发生交换扩散的过程。

RESEARCH ON LEACHING NONSILICEOUS CONSTITUENTS AND ITS MECHANISM

The effects of original glass structure and composition, leaching temperature, time and the concentration of the acid solution on the purity of the drawn sodium-boro-silicate glass fibers without phase separated were systematically studied by using Nuclear Magnetis Resonance (NMR) and Ramanru-1000 Model Raman spectroscopy. The results show that tingh purity and ultrafine silica fibers can be obtained by acid leaching method. The low of leaching monsiliceous constituents was found to be the residual contents of nonsiliceous constituents in the fibers also decrease continually, as the leaching temperature and time increasing, and the decreasing speed gets slower and slower. A minimum point appears on the curve of the residual contents of nonsiliceous constituents vs the acid concentration with acid concentration increasing. Furthermort, leaching mechanism was discussed on the basis of experimental results, which can be considered as a process of ion exchange and diffusion.