Surface Replication and Structural Development in Micromolding for Micro/Nanocomposites

Micromolding with micro-scale surface features of hexagonal boron nitride (h-BN) / polypropylene (PP) composites with different h-BN component was performed to improve molded parts’ heat diffusivity and processability. Effects of h-BN content and process parameters on processability, higher-order structure, and microscale surface patterns of molded parts were analyzed using SEM, WAXD, SPM, and confocal laser scanning microscopy. The replication ratio of the microscale surface pattern and flow length of composite molded parts was improved by compounding the h-BN filler. The replication ratio of the microscale surface pattern near the flow end became greater than 1.0 because of deformation of surface patterns during de-molding. The replication ratio and shape of surface patterns of molded parts were improved with the increase of the h-BN component. The h-BN platelet oriented inside surface micro-features; skin-shear-core structures were well observed in the molded parts.