SiO2-B2O3-Al2O3-ZrO2-RO-R2O系ガラスの分相
1990 年 98 巻 1142 号 p. 1093-1096
詳細
1990 年 98 巻 1142 号 p. 1093-1096
The phase separation of SiO2-B2O3-Al2O3-ZrO2-RO-R2O glasses and the composition of resulting porous glasses were compared with those of conventional Vycor type porous glasses, Phase separation progressed by the nucleation growth mechanism, pore diameter increased with 1/3 power of time. The rate of phase separation in a ZrO2 containing glasses was smaller than that of Vycor type by factors of 1/10-1/100. The rate determining step was considered to be the viscous flow of network structural units. Amounts of Al2O3 and ZrO2 remaining in the SiO2 skeleton increased with increasing temperature and time. The composition of Vycor type porous glasses remained almost constant regardless of the heating conditions.
