Preparation and characterization of porous silica films by a modified base-cagalyzed sol-gel process containing PVA:I.the precursor solution synthesis

摘要

A novel modified base-catalyzed Sol-Gel process containing polyvinyl alcohol (PVA) has been proposed to prepare the porous SiO_2 film. In this process,the growth of the solparticles was artificially borken off and controlled by acid-stabilising agent and PVA. As a resut, a uniform and stable precursor solution was obtained in which the size of sol particles was stable. This new process efficiently overcomes the shortcomings of the traditional basecatalysed Sol-Gel process and can be employed to prepare porous SiO_2 films with desired porosity and thickness. The influence of the catlayst, the reaction temperature, the pH value, the stabilizing agent and the PVA additive on the size of the SIO-2 sol particles is systematically studied in part I.