Mechanical performance of 3D printed polylactide during degradation

Although widely-used biodegradable polymers have been extensively studied for conventional manufacturing processes, this is the first study considering effect of interfacial bonds between extruded filaments – most important aspect related to additive on degradation at 37 °C. Its results improve confidence in material extrusion process and negate one crucial unknown factors bioresorbable products, by demonstrating that interface degrades a similar manner bulk polymer material. To do this, specially designed micro-tensile specimens were developed analyse 3D-printed parts time °C accelerated temperatures. The mechanical properties (Z specimen) compared against control, i.e. along (F specimen), under medically relevant testing conditions (submerged °C). Monitoring tensile strength showed both specimen types behaved similarly, exhibiting an initial delay followed reduction properties. Comparison thermal chemical revealed during early stage degradation, crystallinity was dominating factor, whilst later stages, mainly defined molecular weight autocatalytic degradation. findings suggest understanding long-standing field can be applied additive-manufactured medical devices, which unavoidably contain interlayer interfaces.