Use Of Sol-Gel Method For Introduction And Localization Of Sio2 In Wood: Sio2 ievadisana un lokalizacija koksne, izmantojot sola-gela metodi

Preparation of wood samples and their impregnation with sol-gel solution containing silica. Several technologies of increasing the impregnation efficiency as well as gel localization in sample were investigated. Applying only vacuum during the impregnation procedure it is possible to achieve only 55 - 65 % fill up of total theoretical free pore volume. Additionally use of pressure leads to noticeably higher results and the fill up reaches almost maximum of total theoretical free pore volume. For the investigation of gel localization in the sample, sample pyrolysis and scanning electron microscopy were used. In electron microphotography all three impregnation cycle gel layers can be recognized. It can be seen that introduced gel amount in early wood is significantly bigger than in latewood. It is calculated that after three impregnation cycles dried SiO¬2 gel takes about 25% of total free cell volume.