Examining the Effect of Hexagonal Boron Nitride on Morphological and Chemical Properties of Biopolymers Using Dual-Beam Methodology

Biocompatible and biodegradable polymers have attracted increasing interest for biomedical applications such as drug delivery systems, implants, and medical devices. In this study, nanocomposites based on widely used biodegradable synthetic biopolymers, polylactic acid (PLA) and polycaprolactone (PCL), were investigated to enhance their structural performance. The solvent-dependent effect of hexagonal boron nitride (hBN) addition on the chemical and morphological distribution of silver nanowires (AgNWs) within PCL and PLA matrices was systematically examined. High-resolution morphological characterization was performed using focused ion beam–scanning electron microscopy (FIB-SEM), enabling simultaneous cross-sectioning and imaging. Inner morphology was analyzed by SEM, while elemental distributions were evaluated using energy-dispersive spectroscopy (EDS). The results indicated that hBN incorporation contributed to an improved distribution of AgNWs in both polymer matrices. This effect appeared to be more pronounced in PLA-based nanocomposites prepared using chloroform, where AgNWs showed a comparatively more uniform spatial distribution than in the acetone-prepared samples. In addition, PLA- and PCL-based AgNWs/hBN nanocomposites prepared in chloroform exhibited enhanced mechanical strength and thermal stability during gallium ion milling. Overall, the findings highlight the critical role of solvent selection and hBN incorporation in optimizing the structural properties and performance of biopolymer-based nanocomposites for biomedical applications.