Alargova Rossitza G, Warhadpande Devdutta S, Paunov Vesselin N, Velev Orlin D
Langmuir. 2004 Nov 23;20(24):10371-4. doi: 10.1021/la048647a.
Few foam systems stabilized by solid particles have been reported, and usually the particles have been used in combination with surfactants. We report how foams can be stabilized solely with a new class of anisotropic particles, hydrophobic polymer microrods of diameter less than 1 mum and length of a few tens of micrometers. The obtained foams were extraordinary stable, retaining a constant volume over many days and even surviving drying of most of the free liquid. The bubbles in these foams were sterically stabilized by dense thick "hairy" layers. The rigid intertwined protective shells around the bubbles did not allow the formation of thin films between them. The lifetime of these foams was orders of magnitude longer than the ones stabilized with typical foaming surfactants such as sodium dodecyl sulfate. The addition of sodium dodecyl sulfate led to hydrophilization of the microrods and suppressed the superstabilization effect. Thus, common foaming agents effectively act as defoamers for the ultrastable foams stabilized by microrods.
鲜有关于由固体颗粒稳定的泡沫体系的报道，并且通常这些颗粒是与表面活性剂结合使用的。我们报道了如何仅用一类新型各向异性颗粒——直径小于1微米、长度为几十微米的疏水性聚合物微棒来稳定泡沫。所得到的泡沫极其稳定，在许多天内保持恒定体积，甚至在大部分自由液体干燥后仍能留存。这些泡沫中的气泡通过致密的厚“毛发”层实现空间稳定。气泡周围刚性交织的保护壳阻止了它们之间形成薄膜。这些泡沫的寿命比用典型的发泡表面活性剂（如十二烷基硫酸钠）稳定的泡沫长几个数量级。添加十二烷基硫酸钠会导致微棒亲水化并抑制超稳定化效应。因此，常见的发泡剂对由微棒稳定的超稳定泡沫有效地起到了消泡剂的作用。
