单体和催化剂浓度对PA有机气凝胶结构的影响

Influence of monomer and catalyst concentration on PA organic aerogel structure

以碳酸钠(C)为催化剂、乙醇为溶剂,间苯三酚(P)-乙醛(A)为反应前躯体,经溶胶-凝胶、交联老化、二氧化碳超临界干燥制备出间苯三酚-乙醛有机气凝胶(PA)。PA有机气凝胶的孔结构和密度可以通过改变反应物浓度和间苯三酚与催化剂的摩尔比(P/C)来进行调解。用P/C摩尔比为100、300、500制备一系列不同理论密度PA有机气凝胶。SEM和氮气吸附测试结果表明,单体和P/C的摩尔比主要影响PA有机气凝胶的比表面积、孔容和平均孔径,而对微孔影响不大。

Organic aerogels were synthesized by sol-gel polycondensation of phlorogluctinol（P）with acetaldehyde（A）in a slightly alcohol solution,Na2CO3as the base catalyst,followed by crosslink,solvent exchanging, drying with supercritical carbon dioxide.Pore structure and fact density of PA organic aerogelst can be modified upon variation of the phlorogluctinol to catalyst ratio and by varying the mass ratio of the reactants phlorogluctinol and acetaldehyde in the sol.Here,series of PA organic aerogels have been produced with P/C 100,300and 500,each covering a wide density range.All samples were investigated using SEM and nitrogen adsorption. Surface area,total pore volume and average pore diameters of PA organic aerogelst can be modified upon monomer and catalyst concentration,but has less influence on microporosity.