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采用so1-gel方法制备得间苯二酚/甲醛凝胶(简写为RF gel)。在分析凝胶缩聚物形成基础上,提出改变催化剂种类及用量是调节孔尺度、孔分布的重要途径。对比凝胶形成时间的差异并结合凝胶微观形貌、比表面积表征结果分析,揭示凝胶孔结构调控规律,即分别采用无水Na_2CO_3与Ca(OH)_2作为催化剂,在同样的催化剂含量下,采用无水Na_2CO_3作催化剂得到的凝胶微孔更多:R/C值越小、,反应时间越短,RF凝胶比表面积越大,但当R/C值小于50时,RF凝胶比表面积急剧减小。为在较短的时间内得到大孔容的凝胶骨架,最终确定适宜的工艺条件为,采用无水碳酸钠为催化剂,R/C值等于50,所制备的凝胶孔比表面积在580 m~2/g以上。
The so1-gel method was prepared resorcinol / formaldehyde gel (abbreviated as RF gel). Based on the analysis of the formation of gel polycondensate, it is proposed that changing the type and amount of catalyst is an important way to adjust the pore size and pore distribution. The difference of gel formation time was compared with the results of gel micro-morphology and surface area characterization to reveal the regulation of gel pore structure. That is, anhydrous Na 2 CO 3 and Ca (OH) 2 were used as catalyst respectively. Under the same catalyst content , The average pore diameter of the gel was larger with the anhydrous Na_2CO_3 as the catalyst. The smaller the R / C value was, the shorter the reaction time was, the larger the specific surface area of the RF gel was. However, when the R / C value was less than 50, The specific surface area decreases sharply. In order to obtain a large pore volume of the gel skeleton in a short period of time, the optimum process conditions for the final determination of the use of anhydrous sodium carbonate as a catalyst, R / C value equal to 50, the prepared gel pore specific surface area of 580 m ~ 2 / g or more.