Enhanced Adhesion Properties of Polymer-Metal Interfaces via Nano-injection Molding: A Study on Molecular Kinematic Mechanisms

Nano-injection molding enables the formation of nano-scale anchors to connect heterogeneous material surfaces to achieve the required mechanical properties. In this work, polyphenylene sulfide (PPS), aluminum (Al), copper (Cu), and iron (Fe) were selected as candidate polymer and metal materials. Three kinds of polymer-metal interfacial models with pyramidal nano-slots were modeled. The molecular dynamics simulations were launched to investigate the adhesion properties and molecular kinematic mechanisms of heterogeneous interfaces in nano-injection molding. Results showed that the wall-slipping behavior of PPS at the interface slot was obvious, it was easy to form multiple-anchor-points in the central area of substrates, and these anchor points were easily slipping along the wall, different from the de Gennes model. The atomic lattice and atomic band gap of metal affected the adhesion strength. The BCC lattice of Fe was more suitable for nano-injection molding process than the FCC lattice of Al and Cu. The filling rate, interfacial energy, the tensile and shear failures data revealed that the interfacial adhesion performances decreased according to the following order, Fe-PPS, Cu-PPS and Al-PPS components, respectively, and the interface failure mode was closely related to the stress loading mode.