水灰比对镁系无机轻质材料性能的影响规律

以镁系胶凝材料为主料,双氧水为发泡剂,二氧化锰为激发剂,硬脂酸钙为稳定剂,聚丙烯酰胺为增稠剂,通过化学发泡法制备内部含有大量密闭气孔的镁系无机轻质材料。探讨了水灰比(镁盐水用量与氧化镁粉比率)对镁质无机轻质材料表观密度、压缩强度、弯曲强度、孔结构及耐水性的影响规律。实验结果表明,水灰比不仅影响镁系无机轻质材料的孔结构和发泡成型,对晶体结构也有较大影响。随着水灰比增大,浆体稠度降低,镁系无机轻质材料的表观密度减小,孔结构形态逐渐得到改善,力学强度和耐水性则是先增大后减小。在水灰比为1.4时,强度相峰值最大,镁系无机轻质材料压缩强度和弯曲强度最大,耐水性最佳,同时平均孔径较小,孔隙率和圆度值最接近开普勒理想模型数值,表观密度仅为0.41g/cm~3,适合作为节能轻质墙体材料使用。

Effect of Water Cement Ratio on Properties of Magnesium Inorganic Light Materials

Magnesium inorganic light material containing a large number of closed pores inside were prepared by chemical foaming process, in which magnesium based cementing material as raw material, hydrogen peroxide as foaming agent, manganese dioxide as activator, calcium stearate as stabilizer and polyacrylamide as thickener. The effect of water cement ratio (the ratio of magnesium salt and magnesium oxide) on the apparent density, compression strength, bending strength, pore structure and water resistance of magnesium inorganic light materials were studied. The experimental results showed that the water cement ratio not only affects the pore structure and foaming formation of magnesium inorganic light materials, but also has a great influence on the crystal structure. With the increasing of water cement ratio, the paste consistency decreased, the apparent density of magnesium inorganic light material decreased, the pore structure shape gradually improved, the mechanical strength and water resistance increased first and then decreased. When the water cement ratio was 1.4, the peak of the intensity phase was the largest, the magnesium inorganic light material had the largest compressive strength, flexural strength and best water resistance. At the same time, the average pore size was smaller, the porosity and the roundness value are close to the Kepler ideal model value, and the apparent density was only 0.41 g/cm³, which is suitable for the use of energy-saving lightweight wall materials.