3D printed elastomers with superior stretchability and mechanical integrity by parametric optimization of extrusion process using Taguchi Method

Abstract This study focused on a modified Fused Deposition Modeling (FDM) 3D printing method, specifically the direct pellet printing of a propylene-based thermoplastic elastomer, Vistamaxx™ 6202, to address challenges like printability and weak mechanical properties. The main objective was optimizing printing parameters and investigating their impact on the mechanical properties. The Taguchi method was used to design the experiments, reducing the required experiments and optimizing printing parameters to maximize desired properties. Three influential parameters were chosen, each changing to three levels. By employing the Taguchi method, the number of experiments decreased from 27 full factorials to 9. Regression models were created through analysis of variance (ANOVA) and verified by additional experiments. Tensile tests were performed according to the ASTM D638 standard. SEM imaging was used to assess interlayer adhesion and structural integrity. The results demonstrated satisfactory interlayer adhesion and structural integrity of the printed samples. Notably, the printed thermoplastic elastomers achieved significant stretchability, reaching up to 5921.3%. The tensile strength was 5.22 MPa, with a tensile modulus of 1.7 MPa. The effect of each parameter and their contribution percentage to the tensile strength, elongation, and elastic modulus were obtained from the variance analysis.