Gélinas Stéphanie, Finch James A, Gouet-Kaplan Maxime
Department of Mining, Metals and Materials Engineering, McGill University, 3610 University St., Montreal, Quebec, H3A 2B2, Canada.
J Colloid Interface Sci. 2005 Nov 1;291(1):187-91. doi: 10.1016/j.jcis.2005.04.094.
Methylisobutyl carbinol (MIBC) and methoxy polypropylene glycol (Dowfroth 250) bubble thin films were characterized by composition and thickness determinations, using FT-IR spectroscopy and UV-visible spectrophotometry, respectively. The infrared investigation indicates that the role of frother molecules in creating bubble thin films is based on their effectiveness in inducing H-bonding reorganization of the surrounding free water molecules into a coherent network. From UV-visible interference patterns, it is found that MIBC forms films with a measured critical end thickness of less than 160 nm, compared to 612+/-30 nm for Dowfroth 250. The observed values of the free water layer thickness are comparable at 5.65+/-0.28 microm for MIBC and 6.75+/-0.34 microm for Dowfroth 250. A higher stability of an MIBC bubble over a Dowfroth 250 bubble is related to the different polarization and orientation of the molecules sustaining the boundary surface water network. The findings are used to explain the different action and associated froth characteristics of the two common industrial frothing agents.
分别使用傅里叶变换红外光谱法（FT-IR）和紫外可见分光光度法，通过成分测定和厚度测定对甲基异丁基甲醇（MIBC）和甲氧基聚丙二醇（道弗罗斯250）泡沫薄膜进行了表征。红外研究表明，起泡剂分子在形成泡沫薄膜中的作用基于它们诱导周围自由水分子的氢键重新排列成连贯网络的有效性。从紫外可见干涉图案发现，MIBC形成的薄膜测量临界最终厚度小于160nm，而道弗罗斯250为612±30nm。MIBC的自由水层厚度观测值为5.65±0.28μm，道弗罗斯250为6.75±0.34μm，二者相当。MIBC泡沫比道弗罗斯250泡沫具有更高的稳定性，这与维持边界表面水网络的分子的不同极化和取向有关。这些发现用于解释两种常见工业起泡剂的不同作用及相关泡沫特性。
