Manufacture Dry Porous Carbonate Materials with Crack Free

Abstract

pickering foam is a water foam stabilized using solid particles, and this foam can be used as a material in the production of lightweight porous insulating materials. This is done by pouring it into molds, then drying and finally foaming it. One of the most important problems accompanying the drying of bicarbonate foam is the phenomenon of shrinkage in the models resulting from the liquid leaving it by evaporation, resulting in capillary pressures generated inside it. Due to the shrinkage phenomenon, defects and cracks sometimes occur during the drying process that appear on the surface. The process of defects and cracks formation during the drying process depends on the drying conditions such as temperature, relative humidity, and the type of used support angle θ (in addition to the mechanical specifications of the models). Understanding the drying procedures helps researchers and workers in the production of such porous materials, and in choosing the appropriate drying conditions and avoiding any defects in the product. In this study, the effect of the mechanical specifications of the model was investigated by adding surface tension-reducing agents at different concentrations to the models during the drying process, as well as studying the effect of the contact angle (θ) of the support on the probability of crack formation and the mechanical specifications of the dried model. It was found that the value of the contact angle (θ) has a direct effect on cracks and defects. Increasing the value of the contact angle from θ = 30° to θ = 150° leads to a reduction or treatment of the cracks that appear in the models. It was also found that adding surface tension-reducing agents such as SLES and SDS leads to crack formation in the models, and increasing the concentration of surface tension-reducing agents such as SLES and SDS leads to foam collapse. However, adding surface tension-reducing agents such as C8AC and C10AC did not show any cracks for all concentrations. As for the mechanical properties of the dry models, they are directly affected by the type of surfactant (C10AC and C8AC), which led to the formation of models with porosities higher than 90%. As for the concentration of the surfactant, it has an effect on the wet model, while it does not affect 90%. From the mechanical specifications (porosity and density) of the model after drying