Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, USA.
Langmuir. 2013 Aug 20;29(33):10448-54. doi: 10.1021/la4020306. Epub 2013 Aug 6.
In this paper, we studied the formation of heterogeneous polymer films on ionic liquid (IL) substrates via the simultaneous or sequential depositions of monomers that are either soluble or insoluble in the liquid. We found that the insoluble monomer 1H,1H,2H,2H-perfluorodecyl acrylate (PFDA) only polymerizes at the IL surface, while the soluble monomer ethylene glycol diacrylate (EGDA) can polymerize at both the IL surface and within the bulk liquid. The polymer chains that form within the bulk liquid entrap IL as they integrate into the polymer film formed at the IL surface, resulting in heterogeneous films that contain IL on the bottom side. Varying the order in which the soluble and insoluble monomers were introduced into the system led to different film structures. When the insoluble monomer was introduced first, a film formed at the surface and the soluble monomer then diffused through this film and polymerized within the bulk, leading to a sandwich structure. When the soluble monomer was introduced first, a layered film was formed whose structure followed the order in which the monomers were introduced. When the two monomers were introduced simultaneously, the soluble monomer polymerized in the bulk while a copolymer film formed at the surface. This study provides an understanding of how to control the composition of layered polymer films deposited onto IL substrates in order to develop new composite materials for separation and electrochemical applications.
在本文中，我们通过同时或顺序沉积在液体中可溶或不可溶的单体来研究离子液体（IL）基底上异质聚合物薄膜的形成。我们发现不可溶单体 1H,1H,2H,2H-全氟癸基丙烯酸酯（PFDA）仅在 IL 表面聚合，而可溶单体乙二醇二丙烯酸酯（EGDA）可以在 IL 表面和本体液体中聚合。在本体液体中形成的聚合物链在整合到在 IL 表面形成的聚合物膜中时会捕获 IL，导致含有 IL 的异质薄膜在底部。改变可溶性和不可溶性单体进入系统的顺序会导致不同的薄膜结构。当不可溶单体首先引入时，在表面形成的薄膜，然后可溶性单体通过该薄膜扩散并在本体中聚合，导致三明治结构。当可溶性单体首先引入时，形成层状薄膜，其结构遵循单体引入的顺序。当两种单体同时引入时，可溶性单体在本体中聚合，而共聚膜在表面形成。这项研究提供了一种理解如何控制沉积在 IL 基底上的层状聚合物薄膜组成的方法，以便开发用于分离和电化学应用的新型复合材料。
