Interface Bond Mechanism of EVA-Modified Mortar and Porcelain Tile

摘要

Ethylene-vinyl acetate (EVA) redispersible powder was used to modify mortar. The tensile strength of EVA-modified mortar and the interface bond strength of EVA-modified mortar and porcelain tile, cured under 20 ± 3℃ and relative humidity 50 ± 5%, were tested. The interface bond mechanism of EVA-modified mortar and porcelain tile was discussed. Results obviously showed that EVA redispersible powder improved the tensile strength of mortar. The interface bond strength between EVA-modified mortar and porcelain tile increased with the increase of EVA content in mortar and did not always increase with the extension of curing age. Microstructure analysis illuminated that polymer film was being formed by EVA latex powder along the hydrated products and the mortar-porcelain tile interface. The EVA improved interface bond strength by penetrating the capillary and pore of porcelain tile accompanied with hydrated products.