Study on Microstructures of Complex Plant Polysaccharides Aerogels and Their Effects on Porosity

Abstract

The microstructure of polysaccharide aerogels is a key factor affecting porosity, and directly determines the efficiency of its application as filter rod material. Scanning electron microscopy was used to observe the effects of different amounts of starch on the microstructure of the complex plant polysaccharide aerogels. The experimental results showed that the aerogel samples showed a complete and homogeneous three-dimensional network structure. With the increase of starch content, the pore size became smaller and the pore structure on the hole wall became smaller. After adding starch, the concentration of the system increased, that is, the solute in the unit volume increased, the moisture content decreased, and the air replaced the water in the gel after freeze drying, resulting in the increase of the density of the aerogel and the decrease of porosity. All aerogels showed a trend of increasing filtration efficiency with increasing particle size. The filtration performance of aerogels with different starch content was tested by using the comprehensive performance test bed of filter media. The test results showed that the capture of filter material was mainly through inertial collision. When the particle size was bigger, the greater the inertia, the greater the possibility of particle contamination being captured, so the higher the filtration efficiency.