Research on the properties and mechanism of polymer-modified cement-based high-porosity foam materials

High porosity cement-based foam materials(90%)are prepared by means of mechanical mixing air-entraining method and the effect of polymer powder admixture on the thermal property and mechanical property of foam material is studied.The results show that,under the action of the polymer powder content modification,the material thermal conductivity coefficients are lowered and the mechanics performances are improved to a certain extent and that there exists a certain degree of correlation between the performance improvement of foam materials and polymer powder volume fraction.The maximum compressive strength of 248 kPa and the minimum thermal conductivity of 0.046W/(m·K)are obtained when polymer powder to cement ratio by weight(P/C)is 0.1and 0.2respectively.Impact toughness of polymer-modified foam material is increased significantly with an increase in polymer content.When the P/Cis increased from 0to0.33,the specimen impact energy consumption is increased by 142.3%.The section morphology and pore structure of cement-based foam are observed using SEM and it has been proved that the properties improved of foam material are due to the change in pore wall structure from pure inorganic substance to inorganic-organic complex.