We have recently started exploring the potentialities of high energy radiation processing to consolidate polymeric objects patterned in the 3 dimensions by techniques such as stereolithography (SLA). The successive writing of lines is not favorable to the build-up of structures with optimal cohesion between the printed domains.

We will report here on the EB-induced post-modification of 3D objects printed by SLA applied to acrylate-based resins, with a focus on the changes in monomer conversion, thermophysical characteristics and tensile properties that occur upon application of increasing doses (up to 100 kGy). The strong influence effect of printing orientation with respect to the long axis of the printed specimens was evidenced by measuring the properties of the unirradiated 3D-printed structures. The thickness of the printed layers was also shown to impact the properties of the specimens before irradiation and their evolution after the EB post-treatment.

The improvement of structural features and mechanical properties was shown to be higher after EB-irradiation than for standard combinations of UV and thermal post-treatments. Additional experiments are in progress to investigate the improvement of fracture toughness of 3D-printed specimens by this novel approach using EB-irradiation.