Estudo da adição de celulose em compósito geopolimérico

Abstract

Cellulose reinforced geopolymer matrix plates were produced and characterized. In the geopolymer composition, metakaolin produced from kaolin calcination, cement and silica were used together with potassium hydroxide as alkaline activator. For the characterization of these materials, the X ray diffraction (XRD), X ray fluorescence (FRX) and infrared spectroscopy (FTIR) tests were performed, as well as the cellulose water absorption test. The compression test in the geopolymer matrix was performed at the ages of 1, 3, 7 and 28 days to determine its strength and to determine the age to be performed the subsequent tests. The final resistance at 7 days was found to be equivalent to 76% of the resistance at 28 days, which corresponded to 40.44 MPa. Regarding the four-point flexion tests, the matrix presented similar behavior at the tested ages, presenting an average resistance of 1.95 MPa and 2.04 MPa at the ages of 7 and 14 days, respectively, and presenting a fragile fracture. The composite showed increased strength after first crack stress and great deflection. At the age of 7 days, a resistance of 3.13 MPa was obtained with a deflection of approximately 3 mm, while the age of 14 days had an average resistance of 4.02 MPa corresponding to about 21.95% increase with a deflection around 1.8 mm. The apparent density and water absorption of the matrix showed results of 1.66 g / cm³ and 18.45%, against 1.52 g / cm³ and 21.32% of the composite at 14 days.