Santos, Sergio Francisco [UNESP]Rodrigues, Jose de AnchietaDenzin Tonoli, Gustavo HenriqueFeuzicana de Souza Almeida, Alessandra EtukoSavastano, Holmer2015-03-182015-03-182014-11-01Journal Of Materials Science. New York: Springer, v. 49, n. 21, p. 7497-7506, 2014.0022-2461http://hdl.handle.net/11449/116313The effect of colloidal silica on the hydration reaction of the Portland cement system and its effect on the resulting mechanical properties are not completely understood. Silica nanoparticles can affect the behavior and performance of fiber-cement, such as the calcium-silicate-hydrate gel of the matrix and the fiber-matrix interface bonding. The main objective of this study is to evaluate the effects of various contents of colloidal silica (0, 1.5, 3, 5, and 10 % w/w) on the microstructure and mechanical performance of cement composites reinforced with cellulosic pulp. Fiber-cement composites with unbleached eucalyptus Kraft pulp as the micro-fiber reinforcement were produced by the slurry dewatering technique followed by pressing. The average values of the modulus of rupture of the fiber-cement decreased with increasing colloidal silica content. However, the pullout of the fibers increased significantly in the fiber-cement composites with additions between 3 and 10 % w/w of colloidal silica suspension, as indicated in the scanning electron microscopy images and by the improvement in the energy of fracture values.7497-7506engArtigo10.1007/s10853-014-8455-1WOS:000340679000017Acesso restrito0000-0003-3384-0754