Textural characterization of SiO2-PEG xerogels

The porous SiO2 xerogels with controlled structure were obtained from TEOS in the presence of PEG by sol-gel method. The results showed that PEG restr ained the hydrolysis reaction of TEOS, and then modified the surface of sol particle to form the PEG-clusters (i. e. the ring-like networks in short o rder). As a result, the addition of PEG could adjust the texture properties of SiO2 xerogels, It has been found that the SiO2 xerogel has a stronger f lexible skeleton, narrower pore distribution, and higher thermal stability with the removal of the residue organic(such as PEG and so on) by vacuum he at-treatment.