Study on the potential use of adding crystalline microcelulose in coating mortars

ABSTRACT

Understanding the effects of crystalline microcellulose in rendering mortars is essential for designing more durable, resistant, and efficient construction materials. Therefore, this study aims to verify the influence of adding 0.2%, 0.4%, and 0.6% of crystalline microcellulose (MCC) relative to the cement mass on the fresh and hardened properties of rendering mortars. The study was developed considering the impact of microcellulose additions on the rendering mortars through consistency, (using the flow-table test), bulk density, incorporated air content, and rheological (using the squeeze-flow test), as well as compressive and flexural tensile strength, and dynamic modulus of elasticity. Based on the results obtained, it was concluded that the incorporation of crystalline microcellulose resulted in the consistency of the mortars. At concentrations of 0.2% and 0.4%, there was an increase in air incorporation, plasticity after fifteen minutes of mixing, and a reduction in bulk density, indicating that these percentages may improve the application process, facilitating the execution of rendering mortars. However, after thirty minutes of mixing, a change in rheological behavior was observed, where mortars with crystalline microcelulose addition showed a reduction in displacements compared to the reference, indicating that the high water retention capacity of crystalline microcellulose may influence the plasticity of the mortars over the mixing time. In the hardened state, it was concluded that additions of crystalline microcellulose did not result in improvements in the properties of rendering mortars.

Keywords:
Microcellulose; Cement system; Squeeze-flow; Elastic modulus