Modeling of nano-sized macromolecules in silane-based self-assembled nano-phase particle coatings

Molecular simulation approaches have been used to enhance the understanding of complex chemical interactions in coatings related processes. The Self-assembled NAno-phase Particle (SNAP) coating process relies on aqueous solution processes, similar to those used in conventional sol–gel synthesis, to form siloxane nano-sized structures, which are subsequently cross-linked upon film application. This process has been shown to produce a dense, protective thin film on metal substrates. The SNAP process involves design and selection of the coating constituents, based on the desired functionalities for network formation and cross-linking chemistry. In order to facilitate the design of coating components at the molecular level, it is imperative to gain a fundamental understanding of these complex phenomena. Molecular simulations on several oligomers with different side chains have been performed to study components of the of Si–O networks during the SNAP particle formation process. Several ring structures of tetramethyl orthosilicate (TMOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) have been considered. Geometry optimization of the cyclic Si–O structure formation has been performed, and ring strain parameters have been calculated.