Influence of the nano TiO2 dispersion procedure on fresh and hardened rendering mortar properties

Autor: Kai Loh, Ramoel Serafini, Sérgio Roberto Andrade Dantas, Fúlvio Vittorino, Roberto Cesar de Oliveira Romano
Rok vydání: 2019
Předmět:
Zdroj: Construction and Building Materials. 215:544-556
ISSN: 0950-0618
DOI: 10.1016/j.conbuildmat.2019.04.190
Popis: This study was carried out to evaluate the influence of n-TiO2 dispersion on fresh and hardened rendering mortar properties. Five compositions were evaluated with dispersed polypropylene microfibers (PPMF): a reference, without n-TiO2 addition, and four using two commercial samples of n-TiO2, evaluated in two dispersion conditions. Although the materials were the same in all formulations, the water content was modified to maintain the same mortar consistency as determined by flow table results. The fresh properties of the mortars were determined by means of squeeze flow and air-entrainment tests, while hardened properties were evaluated by capillary water absorption, air-permeability, dynamic elastic modulus, drying shrinkage, split tensile strength according to the Brazilian test, and porosity by the Archimedes immersion method. The results obtained have shown that the fresh and hardened mortar properties were affected by the dispersion procedure and the properties of the n-TiO2 samples, indicating that the addition of n-TiO2 in a dispersed form was more effective to control fresh and hardened mortar properties. On the other hand, drying shrinkage results are not influenced by the dispersion procedure but as of the characteristics of n-TiO2.
Databáze: OpenAIRE