Molecular Dynamics Simulation of the Interface Formation of Carbon Nanotube/Crystalline and Amorphous Thermoplastic Resin Composites
In order to study the differences of structure,orientation and energy changes during the interfacial formation of single-walled carbon nanotube/crystalline and amorphous thermoplastic resin composites,built the bridge between microstructure and macroscopic properties,molecular models of single-walled carbon nanotubes/polypropylene(SWCNT/PP),single-walled carbon nanotubes/polyethylene(SWCNT/PE)crystalline,single-walled carbon nanotubes/polystyrene(SWCNT/PS),single-walled carbon nanotubes/polymethyl methacrylate(SWCNT/PMMA)amorphous thermoplastic resin composite systems were established by molecular dynamics simulation.The forming process of the interphase was simulated,radial distribution function,interface energy and total energy were calculated.The simulation results showed that the formation process of the interphase of the SWCNT/PS and SWCNT/PMMA were mainly adsorption.While the formation process of the interphase of the SWCNT/PP and SWCNT/PE were divided into adsorption and orientation.The g(r)of the SWCNT/PP and SWCNT/PE firstly decreased sharply in the range of r,then the value of the g(r)increased sharply,therefore the interphase crystallized,forming a short-range ordered structure.At 2 000 ps,the interfacial energy of the SWCNT/PP and SWCNT/PE were-620.1 kcal/mol and-791.7 kcal/mol,which were smaller than that of the SWCNT/PS and SWCNT/PMMA,so the interface bonding were better.The total energy of the SWCNT/PP and SWCNT/PE decreased gradually,which were-1 654.9 kcal/mol and-1 211.2 kcal/mol at 2 000 ps.Compared to the SWCNT/PS and SWCNT/PMMA,the total energy of the SWCNT/PP and SWCNT/PE were smaller,and the composite system were more stable.
Molecular dynamics simulationOrientation crystallizationRadial distribution functionInterfacial energy