Journal of Colloid and Interface Science, Vol.392, 256-265, 2013
Formation and structure of Langmuir-Blodgett films of organo-modified aluminosilicate with high surface coverage
We have developed an effective organo-modification method at the organic solvent/distilled water interface of natural aluminosilicate clay surfaces. We also investigated the molecular arrangement of organo-modified aluminosilicate with high surface coverage in Langmuir-Blodgett films (LB) by performing out-of-plane and in-plane X-ray diffraction (XRD) measurements. In addition, the surface morphology of mixed monolayers of organo-modified aluminosilicate and several biodegradable polymers (e.g., poly (L-lactide), PLLA) was also characterized by atomic force microscopy (AFM). The in-plane XRD results of multilayers of organo-modified aluminosilicate formed by the LB method indicate the formation of a two-dimensional lattice of hydrocarbons on the aluminosilicate surface. These hydrocarbons of organo-modified reagents packed hexagonal or orthorhombic in films. Based on our experimental findings, the LB technique enabled the formation of a densely packed organo-modified aluminosilicate monolayer at the water surface. Furthermore, for mixed monolayer systems comprising an organo-modified clay with high surface coverage and biodegradable polymers, a miscible surface was observed by AFM on a mesoscopic scale, whereas those with low surface coverage formed phase-separated structures. (c) 2012 Elsevier Inc. All rights reserved.
Keywords:Langmuir-Blodgett films;Organo-modified aluminosilicate;Surface coverage;Molecular arrangement;Miscibility