In order to enhance the resistance to aging and the permeability of acrylate polymers used for the protection of damaged pottery, a series of in situ composites was synthesized starting with sol containing tetraethoxysilane, which was added to polyacrylate. The color, thermal resistance, molecular structure and microstructure of composites were evaluated by spectrophotometric, DSC, ATR - ITIR and SEM techniques. Important features of material performance, such as compressive strength and vapor permeability, were tested for the consolidated pottery samples. The results indicated that the in - situ composites had favorable interaction between silica and acrylate copolymer, and that the addition of nano silica improved the thermal stability of the material and prevented photo - degradation. The compressive strength and the vapor permeability of the damaged pottery were improved, especially in materials in which 5 % to 10% tetraethoxysilane had been added.