摘要
In order to improve the spinnabilities of A95 alumi- na silica sols, the influences of addition and polymeriza- tion degree of polyvinyl alcohol on spinnabilities of alu- mina silica sols were researched. The viscosity and rheo- logical properties of the sols, mierostructure, infrared spectra, average diameter and diameter distribution oJ the gel fibers, BET specific surface area and distribution of pore diameters were measured. The results show that iJ there is no spinning agent, the A95 sols have no spinna- bility ; when PVA 2099 addition is in the range of l. 0% -2.0% （in mass, the same hereinafter） , the prepared sols have good spinnability, the gel fibers produced are thin and uniform, and the shot content is low ; BET spe- cific surface area and gas absorption amount of A95 polycrystalline alumina fibers are the largest when PVA 2099 addition is 2. 0% ; the gel fibers are thick and non-uniform, and the shot content is high when PVA 2099 addition is 4. 0% ; with polymerization degree oJ PVA increasing, the average diameter and diameter dis- tribution range of the gel fibers increase gradually; when using PVA 1799 and PVA 1899, respectively, the spun gel fibers are thin and uniform.
In order to improve the spinnabilities of A95 alumi- na silica sols, the influences of addition and polymeriza- tion degree of polyvinyl alcohol on spinnabilities of alu- mina silica sols were researched. The viscosity and rheo- logical properties of the sols, mierostructure, infrared spectra, average diameter and diameter distribution oJ the gel fibers, BET specific surface area and distribution of pore diameters were measured. The results show that iJ there is no spinning agent, the A95 sols have no spinna- bility ; when PVA 2099 addition is in the range of l. 0% -2.0% （in mass, the same hereinafter） , the prepared sols have good spinnability, the gel fibers produced are thin and uniform, and the shot content is low ; BET spe- cific surface area and gas absorption amount of A95 polycrystalline alumina fibers are the largest when PVA 2099 addition is 2. 0% ; the gel fibers are thick and non-uniform, and the shot content is high when PVA 2099 addition is 4. 0% ; with polymerization degree oJ PVA increasing, the average diameter and diameter dis- tribution range of the gel fibers increase gradually; when using PVA 1799 and PVA 1899, respectively, the spun gel fibers are thin and uniform.
