Key Laboratory for Colloid and Interface Chemistry of the Education Ministry, Shandong University, Jinan, Shandong 250100, People's Republic of China.
J Colloid Interface Sci. 2010 Mar 1;343(1):87-93. doi: 10.1016/j.jcis.2009.10.081. Epub 2009 Nov 5.
The addition of salt promotes the adsorption of layered double hydroxide (LDH) particles onto the air-water interface, but stable foams cannot be prepared from LDH dispersions at all the concentration of NaCl or sodium acetate. We generated stable foams using positively charged plate-like LDH particles in the presence of sodium butyrate. The effects of adding sodium butyrate to LDH on the particle zeta potential, adsorption behavior and the adsorption of modified particles at the air-water interface were studied. At a fixed LDH particle concentration, adding of a trace amount of sodium butyrate maximizes flocculation of the aqueous particle dispersion. Foams prepared under this condition of particle dispersion are most stable to coalescence and halt completely disproportionation. Also, the size of the bubbles is the smallest. The bubbles are stable when drying at 80 degrees C with little change in size. Laser-induced fluorescent confocal micrographs and scanning electron microscopy observations clearly confirm the adsorption of LDH particles on the foam surfaces, and the bubbles are armored by an interfacial particle multilayer.
盐的添加促进了层状双氢氧化物（LDH）颗粒在气-水界面上的吸附，但在所有氯化钠或醋酸钠浓度下，都无法从 LDH 分散体中制备出稳定的泡沫。我们在正电荷板状 LDH 颗粒的存在下使用丁酸钠生成了稳定的泡沫。研究了向 LDH 中添加丁酸钠对颗粒 ζ 电位、吸附行为以及改性颗粒在气-水界面上的吸附的影响。在固定的 LDH 颗粒浓度下，添加痕量的丁酸钠可最大限度地絮凝水相颗粒分散体。在这种颗粒分散体的条件下制备的泡沫对聚结最稳定，并且完全停止歧化。此外，气泡的尺寸最小。当在 80°C 下干燥时，气泡很稳定，尺寸几乎没有变化。激光诱导荧光共焦显微镜和扫描电子显微镜观察清楚地证实了 LDH 颗粒在泡沫表面上的吸附，并且气泡被界面颗粒多层所保护。
