新型纳米甲酚-甲醛气凝胶的制备及表征

PREMRARATION AND CHARACTERIZATION OF ORGANIC AEROGELS FROM CRESOL MIXTURE WITH FORMALDEHYDE

首次以混甲酚（Ｊ）和甲醛（Ｆ）为原料，在 ＮａＯＨ（Ｃ）催化作用下制备混甲酸甲醛气凝胶（ＪＦ），考察了制备条件与气凝胶性能的关系，并用 ＴＧ、 ＴＥＭ、 ＮＭＲ、 ＦＴ—ＩＲ、 Ｎ２吸附表征了气凝胶结构．结果表明，ＪＦ气凝胶的密度随反应物浓度和催化剂含量的增加而增加，混甲酸与甲醛溶胶－凝胶过程中形成的交联键是亚甲基醚键和亚甲基键，ＪＦ气凝胶紧可几孔径约３０ｎｍ，网络粒子直径约 ２０ｎｍ，是典型的中孔材料．有机气凝胶热解可以得到炭气凝胶，在 ３００～６００℃ 之间 ＪＦ气凝胶失重显著．

Aerogels are firstly prepared through polymerization of cresol mixture with formaldehyde catalyzed by NaOH in this paper. The relation between aerogels properties and contents of reactant and catalyst are investigated while the microstructure of aerogels are investigated through TG, TEM. NMR, FT--IR, N2 absorption technique. The results showed the density of JF aerogels increased with reactant concentration and catalyst content increase. CH2--O--CH2 and --CH2 were main crosslinking bond formed in sol--gel process. JF aerogels were typical mesoporous materials whose pore size is concentrated on 30nm or so, the weight loss of JF aerogel became significant in the range of 300-600 ℃, then got smooth beyond 600 ℃.