一种均一孔结构模型的制备和表征

对于８５～１０００ｎｍ的无孔单分散二氧化硅颗粒，采用重力沉降、离心沉降和压片等方法制备了孔结构模型，并采用扫描电镜（ＳＥＭ）、Ｎ２吸附法和压汞法考察了模型的结构特点。这种孔结构模型完全排除了微孔的存在，孔分布集中，孔径大小随着颗粒粒径的变化而变化，但孔隙度与粒径基本无关。由这３种方法得到的孔结构模型的孔隙度均小于３５％，孔径都没有超出球形颗粒不同的有序排列形式的间隙孔尺寸的理论范围（０．１５５～０．７３２倍粒径）。颗粒粒径的大小、制备方法对孔结构模型的结构有一定的影响

PREPARATION AND CHARACTERIZATION OF A SORT OF POROUS STRUCTURE MODELS WITH UNIFORM PORE SIZE

he models for pore structures of 851 000 nm nonporous monodispersed silica particles were made by using gravity settling, centrifugation and pelletization. The characteristics of models were investigated by scanning electron microscopy (SEM), nitrogen sorption and mercury porosimetry. The results indicate that there are no micropores in the models, and the pores are narrowly distributed. Although the pore size changes with the particle size, the porosity is almost independent of pore size. The porosities are all less than 35%. The way of preparation and the size of particles have some influence on the pore structure of models.\=