Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Graphical representation of the fabrication and characterization workflow.

ABSTRACT
This study investigates the effect of process parameters on the tensile strength (TS) and surface roughness (SR) of nano-graphene nanoplatelet (GNP) reinforced photopolymer composites produced by stereolithography (SLA). Although SLA offers high surface quality compared to other 3D polymer printing methods, the low mechanical strength of resin-based parts limits structural applications. In this context, the main objective of the study is to determine the effects of layer thickness (0.02–0.06 mm), exposure time (20–30 s), and GNP ratio (0.1%–0.3%) on TS and SR using response surface method (RSM) experimental design, and to determine optimum production conditions. According to the results obtained, the highest TS was obtained as 40.74 MPa in the sample with a layer thickness of 0.02 mm, an exposure time of 20 s, and 0.3% GNP. ANOVA results showed that layer thickness and GNP ratio were statistically significant on TS and SR, while exposure time, although not effective alone, played a significant role in interaction with GNP ratio. FTIR, XRD, SEM, XPS, and TG–DSC analyses revealed that GNP addition strengthened resin-reinforcement interface interactions and improved microstructural integrity. Thus, by selecting optimum parameters, high-performance GNP-reinforced composites could be produced using the SLA 3D printing method.