Production of multifunctional nanoparticle-reinforced polymer composite surfaces by photopolymerization method and investigation of performance characteristics

In the recent years, Stereolithography (SLA) type three-dimensional (3D) printers have gained increasing importance in the production of composite materials due to their high precision, low surface roughness, and minimal material waste. Also known as additive manufacturing (AM), 3D printing enables the fabrication of complex geometries that are difficult or impossible to achieve with conventional manufacturing techniques. This technology offers design flexibility and production efficiency, making it widely used in biomedical, automotive, aerospace, and defense sectors [1,2]. SLA technology, first introduced in the 1980s using UV lasers, is based on the principle of layer-by-layer polymerization of liquid photopolymer resins via computer-controlled ultraviolet light. During the process, semi-liquid raw materials are solidified into high-resolution and dimensionally accurate geometries. The mechanical, thermal, and electrical properties of parts produced using SLA can be precisely optimized compared to conventional production methods. With recent technological advancements, research on the fabrication of nanocomposite materials via SLA has significantly increased. The design freedom, cost-effectiveness, and production speed offered by SLA technology have accelerated investigations in this field. In this thesis, nanocomposite surfaces were fabricated by incorporating nanoparticles into a photopolymer resin with concentrations of 1%, 3%, and 5%. The specimens were produced layer-by-layer using an Anycubic SLA printer with a layer thickness of 50 microns. Surface resistivity measurements were performed in accordance with the TS EN 1149-1:2006 using an ELME Multimeg device under controlled conditions of 25°C and 50% relative humidity. The results indicated that all samples exhibited surface resistivity values exceeding 1012 ohms, confirming their high electrical insulation performance. Additionally, antibacterial activity tests, conducted in accordance with TS ISO 22196, revealed that all formulations exhibited more than 99% effectiveness against S. aureus and E. coli. Electromagnetic shielding effectiveness (EMSE) was evaluated based on scattering parameters, and the materials demonstrated a shielding effectiveness of less than 5 dB in the 8–12 GHz frequency range. Consequently, the developed nanocomposites show potential for use in applications requiring electrical insulation, antimicrobial surfaces, and partial permeability to electromagnetic waves. Keywords : SLA resin, 3D printer, photopolymer, additive manufacturing, composite materials