铺展溶剂对气/水界面上C_(16)OH不溶膜的影响

Effects of Spreading Solvent on Insoluble Film of 1-hexadecanol at the Air/Water Interface

文章探讨了不同铺展溶剂对十六醇（C16OH）不溶膜在空气／水界面上的性能的影响。测试了铺展系数和成膜功，π-t等温线和r-t等温线，并用AFM观察了不同溶剂下的C16OH不溶膜形貌。结果表明以石油醚（30℃～60℃）为铺展溶剂的不溶膜铺展效果最好，铺展15min后，π就达到25mN／m以上，30min以后，π趋于稳定。且石油醚（30℃-60℃）在不溶膜中的残留最少，抑制水分蒸发的效果最好。不溶膜的AFM图像显示，以石油醚（30℃～60℃）作为铺展溶剂的不溶膜结构更紧密，凝聚性更好，膜的缺陷更少，因此抑制水份蒸发的效果更好。

This paper examines the effects of spreading solvent on insoluble film properties of 1 -hexadecanol （C16OH） at the air/water interface. Film forming work, spreading coefficient, π -t isotherm and r -t isotherm are shown to explain spreading behaviors of C16 OH film. AFM provides topography of C16OH film spreaded from five different solutions. The results show that petroleum ether （30℃ -60 ℃ ） can spread C16OH film best on the water surface. Its surface pressure at- tains over 25 mN/m after initial spreading of 15min and yields a metastable value of surface pressure after only 30 min. Besides, the fewest solvent molecules of petroleum ether （30 ℃ -60 ℃） are obstructed in the insoluble film, and the effect of inhibiting water evaporation is best. The relatively condensed surface topography of the C16 OH film from petroleum ether （30℃-60 ℃） could be observed with the less defective surface. Thus, petroleum ether （30℃ - 60℃） might be better for the use as spreading solvent compared with other four solvents.