This study investigates and analyzes the major characteristics of naturally occurring asbestos (NOA) in the Seosan area, based on a geological map of NOA distribution. The study area includes Daesan-eup, Seokmun-myeon, and Palbongmyeon in Seosan-si, Chungcheongnam-do, South Korea, with 32 samples collected from nine sites. The asbestos-containing rocks primarily consist of dolomite, limestone, calcareous silicate rock, and marble, most of which exhibit a mass-fiber morphology. While the weathering grade of the outcrops is generally within level 3, some areas show higher weathering levels (grade 4), indicating potential risks of asbestos dispersion into the air. The collected samples were analyzed using polarized light microscopy (PLM), X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), and transmission electron microscopy with energy-dispersive spectroscopy (TEM-EDS). The primary asbestos types identified were tremolite and actinolite asbestos of the amphibole group, with anthophyllite asbestos detected in some locations. Notably, certain asbestos-containing rocks were found near coastal areas and docks, highlighting the need for continued monitoring in the event of future development activities.
In this study, a composite material suitable for flexible transparent electrodes was fabricated using Norland Optical Adhesive 68 (NOA 68), an ultraviolet (UV) curable polymer, and silver nanowires (Ag nanowire, AgNW). The mechanical behavior of this composite was then analyzed. A AgNW network structure was embedded in the NOA 68 polymer and cured using UV energy. The composite was prepared with an AgNW network structure formed approximately 4 μm from the top of the NOA 68 matrix. Tensile test specimens were prepared according to ASTM standards, and tensile tests were conducted at room temperature in air. Scanning electron microscopy (SEM) and tensile tests were used to analyze the changes in mechanical behavior according to UV exposure time and the presence of AgNW. The results showed that as UV curing time increased, the yield strength of the composite increased while the elongation decreased. Regardless of the presence of the AgNW filler, the stress-strain curves of the ductile polymer exhibited the typical mechanical behavior of semi-crystalline polymers as UV curing time increased, characterized by strain softening. It was also confirmed that the composite impregnated with AgNW exhibited higher strength in response to changes in mechanical properties due to UV curing.