Identifying Syndiotactic Polypropylene as a Promising Candidate for Polymer Laser Powder Bed Fusion and Neutron Shielding Materials

With the development of nuclear energy technology for microreactor power sources, shielding components with complex geometries is becoming increasingly important. However, conventional manufacturing methods, such as compression and injection molding, are limited to producing two-dimensional plate-shaped products. In this study, syndiotactic polypropylene (sPP) was demonstrated to be an ideal material for powder bed fusion of polymers using a laser beam (PBF-LB/P), due to its low crystallinity and wide sintering window (SW). Under a laser power of 40 W and a scan spacing of 0.3 mm, the sintered sPP specimens exhibited a tensile strength of 16.54 MPa, an elongation at break of 15.4%, a warping degree of only 1.42°, and a dimensional deviation of less than 0.4 mm. Compared to other polymers processed by PBF-LB/P, sPP’s high hydrogen content shows promising potential for neutron-shielding structural parts. Therefore, this study not only advances the processing of sPP in PBF-LB/P technology but also provides new insights into the development of complex, lightweight shielding components.