Gel formation and gel drying. According to Sohu's query. Carding, gel formation and gel drying. The realization of aerogel principle depends on two basic processes: gel formation and gel drying. In the process of gel formation, molecules or ions form aggregates through chemical reactions or physical changes in solution, and these aggregates form a three-dimensional network structure in liquid, that is, gel. In the process of gel formation, it is necessary to control the reaction conditions, such as temperature, PH value and reaction time, to ensure the gel formation and special properties.