title: A molecular model for epsilon-caprolactam-based intercalated polymer clay nanocomposite: Integrating modeling and experiments.
abstract: In studying the morphology, molecular interactions, and physical properties of organically modified montmorillonite (OMMT) and polymer clay nanocomposites (PCNs) through molecular dynamics (MD), the construction of the molecular model of OMMT and PCN is important. Better understanding of interaction between various constituents of PCN will improve the design of polymer clay nanocomposite systems. MD is an excellent tool to study interactions, which require accurate modeling of PCN under consideration. Previously, the PCN models were constructed by different researchers on the basis of specific criteria such as minimum energy configuration, density of the polymer clay nanocomposite, and so forth. However, in this article we describe the development of models combining experimental and conventional molecular modeling to develop models, which are more representative of true intercalated PCN systems. The models were used for studying the morphological interactions and physical properties. These studies gave useful information regarding orientation of organic modifiers, area of coverage of organic modifiers over the interlayer clay surface, interaction of organic modifiers with clay in OMMT, interaction among different constituents of PCN, conformational and density change, and actual proportion of mixing of polymer with clay in PCN. We have X-ray diffraction and photoacoustic Fourier transform infrared spectroscopy to verify the model.
authors.affiliation: Department of Civil Engineering, North Dakota State University, Fargo, North Dakota 58105, USA.
authors.forename: Debashis
authors.initials: D
authors.lastname: Sikdar
authors.forename: Dinesh R
authors.initials: DR
authors.lastname: Katti
authors.forename: Kalpana S
authors.initials: KS
authors.lastname: Katti
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D001546:Bentonite / Q000737:chemistry; D002209:Caprolactam / Q000737:chemistry* / Q000145:classification; D000077215:Clay; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008958:Models, Molecular; D015394:Molecular Structure; D053761:Nanocomposites / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D011108:Polymers; D014867:Water; D001546:Bentonite; D002209:Caprolactam; D010100:Oxygen; D000077215:Clay