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Four different consolidants for adobe buildings conservation were synthetized and evaluated. Adobe bricks materials tested from several Mining Haciendas of the seventeenth and eighteenth centuries located in Guanajuato, Mexico; these materials were characterized using XRD analysis, granulometry, porosity, moisture content, and mechanical resistance. The four consolidants synthetized are formulations based on TEOS (F1); TEOS with silica nanoparticles (F2); TEOS with PDMS-OH (F3) and hybrid consolidant formed by TEOS, PDMS, and nanoparticle silica (F4). The consolidants were tested and evaluated by porosity changes, absorption, and durability. The results show that colloidal silica improves the fulfill porosity by TEOS gels and the PDMS improves the flexibility on TEOS gel avoiding the crack. Thus, the addition of both components to TEOS gel results as an excellent consolidant treatment to adobe materials.

Hybrid silica coating obtained from TEOS and PDMS using Methyl, Phenyl and Amino as functional groups of siloxane chain were obtained using Dibutyl-dilaurate tin (DBTL) as a neutral poly-condensation catalyst under free solvent conditions. The hybrid silica coating was characterized using different characterization techniques. FT-IR shows the presence of main functional groups for silica network and PDMS. On the other hand, TGA confirmed the formation of coatings with 76%w of ceramic yield. The C1s XPS peak analysis shows that only 30% of organic material corresponds to alkoxy groups without hydrolyzer from TEOS. Furthermore, Si2p peak XPS analysis shows that around 30% of ceramic network corresponds to Si-D and similar concentration to Q2 silicon species, which are found binding to siloxane chain from PDMS. Similarly, the Sn concentration on hybrid silica network was negligible according to Sn3d peak XPS. Furthermore, the corrosion resistance analysis for the different ceramic shows that the amino and phenyl groups improve the corrosion resistance for aluminum according to NACE international criteria.