Effect of Anti-Cracking Agent on Cracking Property of SiO_2 Optical Fiber Preform by Sol-Gel Method

摘要

Optical fiber preform is the core in the industry of optical fiber manufacturing, and vapor deposition is used in general internationally of which the raw material is expensive and the craft is complex. To reduce the cost of optical fiber, we selected tetraethoxysilane(TEOS) and H_2O as raw material, ethanol as solvent, hydrochloric acid (HCl) and ammonia water as catalyst, in the condition of using different anti-cracking agent, including formamide(CH_3NO), oxalic acid (C_2H_2O_4), polyethyleneglycol 2000 (HO(C_2H_4O)nH), N, N-dimethylformamide(C_3H_7NO) and glycerol(C_3H_8O_3), to prepare SiO_2 Dry gel by sol-gel method in this paper. This paper mainly researched on the effect of anti-cracking agent on the cracking property of SiO_2 Dry gel. The XRD analysis indicated that the samples' microstructures were amorphous. All kinds of anti-cracking agent were worked, but the effect on anti-cracking was different, and the dry gel which was added C_3H_7NO was smooth and optimum, which were confirmed by the results of SEM. The analysis of the transmittance showed that the transmittance of dry gel with C_3H_8O_3 was more than 92 percent.