Effect of polyvinyl alcohol on the performance of carbon fixation foam concrete

Abstract

The introduction of carbon fixation components (calcium hydroxide) can improve the carbon fixation performance of foam concrete, however, it will reduce its mechanical properties. In order to solve the adverse effects of carbon fixation components on the mechanical properties and optimize carbon absorption properties, a specific amount of polyvinyl alcohol (PVA) is incorporated. In this study, a serial of test was employed to study the production process of nano-modified foam, and some basic properties of the foam concrete of interest. Further, the micromorphology and pore structure of the samples were analyzed by scanning electron microscope and mercury injection test. The evolution of mineral phases was examined by X-ray diffraction and thermogravimetric analysis. The results show that the carbon sequestration efficiency of foam concrete increases significantly as the amount of calcium hydroxide is increased, however, the cementitious properties of materials deteriorate, resulting in a decrease in strength. When PVA is added as a water-soluble admixture, it can enhance the mechanical properties of test blocks. It can also strengthen the bubble film of nano stabilized foam, increase bubble stability, and refine the internal pore structure of carbon fixation foam concrete. In addition, PVA can modify the calcium hydroxide morphology from a laminar structure to a smaller volume edge corrosion structure, which improves the reaction activity of calcium hydroxide with CO2 and boosts the efficiency of carbon sequestration.