单体法制备MF气凝胶工艺

Preparation of MF Aerogel Prepared with Monomer

以三聚氰胺(M)和甲醛(F)为原料,经溶胶-凝胶和超临界干燥过程成功制备出MF气凝胶。实验详细研究了反应物总浓度、溶液pH值、温度等对凝胶化时间及其结构的影响,实验结果表明:在一定的浓度和pH值范围内,凝胶化时间随反应物总浓度增加而减少,随pH值的降低而减少;只有在一定的pH值范围内(1.4～1.8)才能制得透明的MF气凝胶,反应物总浓度增大,孔径分布较窄且均匀(1～3 nm)。

MF aerogel was prepared from Melamine（M） and Formaldehyde（F） by sol-gel and supercritical drying process. In the experiment we studied the relation between the total concentration,pH ,temperature,gelation time and structre. The results indicated that in the specifically pH and temperature, the gelation time of MF aerogel reduced when the total concentration or pH of the solution increased, transparent MF aerogel was given in the stated pH （ 1.4 - 1. 8） and size distribution became narrow and even（ 1-3 nm） when the reactant concentration increased.