Organic xerogels,  m-Substituted phenols, TG-MS study,  Polycondensation,  Pyrolysis,  Reactivity

Four samples of organic xerogels have been prepared by polycondensation of different m-substituted phenols (3-aminophenol, m-cresol, phenol and resorcinol) with formaldehyde and subsequent drying. The reactivity of the m-substituted phenols was ascertained in the order phenol\m-cresol\resorcinol\3-aminophenol. Phenol and m-cresol did not completely react with formaldehyde during polycondensation reactions. The used type of m-substituted phenol strongly influenced the properties of the final material. The pyrolytic process has been evaluated by TG- MS as three-step process. The first step was characterised as volatile substances loss (n-butanol andwater) and mostly CO2 evolution, the second step as evolution of the rest volatiles and the beginning of the carbonisation processes,whilst during the third step merely carbonisation reactions occurred. On the basis of all considered results, 3-aminophenol has been evaluated as the most appropriate precursor for carbon xerogel preparation.