Yasui Kyuichi, Tuziuti Toru, Kanematsu Wataru
National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan.
Langmuir. 2021 Feb 9;37(5):1674-1681. doi: 10.1021/acs.langmuir.0c02844. Epub 2021 Jan 26.
The experimental results [Kanematsu, W. 2020, 219, 115594] on the temporal variations of number concentrations of bulk nanobubbles (ultrafine bubbles) in contact with polymer materials are theoretically analyzed based on the dynamic equilibrium model of bulk nanobubbles partly covered with hydrophobic materials (impurities). It is suggested that bulk nanobubbles are adsorbed on a polymer surface by attractive hydrophobic interaction between a polymer surface and a hydrophobic material partly covering the bubble surface, overcoming the repulsive double-layer interaction. There are two mysteries. One is that the maximum surface number concentration of bulk nanobubbles of about 70 nm in diameter adsorbed on a hydrophobic polymer surface is more than an order of magnitude lower than the typical value for colloid particles of a similar or larger size. The other is that the experimental adsorption rate of bulk nanobubbles on hydrophobic polymer surface is several orders of magnitude than the theoretically estimated one. The mysteries are resolved if many of the bulk nanobubbles adsorbed on a hydrophobic polymer surface change to surface nanobubbles with a footprint diameter of about 1 μm.
基于部分覆盖有疏水材料（杂质）的体相纳米气泡的动态平衡模型，对[金松，W. 2020，219，115594]中关于与聚合物材料接触的体相纳米气泡（超细气泡）数浓度随时间变化的实验结果进行了理论分析。研究表明，体相纳米气泡通过聚合物表面与部分覆盖气泡表面的疏水材料之间的疏水吸引相互作用吸附在聚合物表面，克服了排斥性的双层相互作用。存在两个谜团。一个是吸附在疏水聚合物表面的直径约70 nm的体相纳米气泡的最大表面数浓度比类似尺寸或更大尺寸的胶体颗粒的典型值低一个多数量级。另一个是体相纳米气泡在疏水聚合物表面的实验吸附速率比理论估计值高几个数量级。如果吸附在疏水聚合物表面的许多体相纳米气泡转变为足迹直径约为1μm的表面纳米气泡，这些谜团就能得到解决。
