(748f) Multiscale Simulation of the Atomistically Tailored Polymers / Oligomers Films and Surface Characterization

Molecularly thin film materials have emerged as a highly interesting and useful functionality for the numerous sustainable nanotechnology applications ranging from protective and smart coatings to electronics and nano-mechanical systems, sensors, renewable energy systems, display technology as well as serving biological, analytical, and medical purposes. Since peculiar phenomena were observed by the coupling of functional groups (e.g., dewetting), the control parameters of the molecular conformations and morphologies of polymeric / oligomeric films by tailoring the molecular structure and functionality are a key to achieving the enhanced film properties for the design of application-driven nano-components. In order to facilitate the analysis of experimental data and enable predictive engineering of such systems, solid theoretical understanding is necessary. In this study, we investigated the variation of molecular conformations and surface morphology of functional oligomers with atomistically tailored structure and functionality. Molecular dynamics simulation using a coarse-grained, bead-spring method was performed to generate the morphology from submonolayer to a few layer oligomeric films [1]. To characterize the surface morphology, we introduced the wavelet transform entropy [2] as well as correlation length and the roughness exponent. Different morphological states were found for various oligomers backbones, resulting from strong tethering of functional groups on the solid surface, and as a function of surface coverage. In addition, the correlation between the surface morphologies, transport properties, and the wavelet entropy will be given.

[1] P.S. Chung, et al., J. Appl. Phys., vol. 103, p. 07F526 (2008).

[2] M.H. Bharatil, et al., Chemometr. Intell. Lab., vol. 72, p. 57 (2004).