Influence of Thermal Annealing on the Sinterability of Different Grades of Polylactide Microspheres Dedicated for Laser Sintering

We present a comparison of the influence conditioning temperature microspheres made medical grade poly(L-lactide) (PLLA) and polylactide with 4 wt % D-lactide content (PLA) on thermal structural properties. The were fabricated using solid-in-oil-in-water method for applications in additive manufacturing. annealed below glass transition (Tg), above Tg but onset cold crystallization, at two temperatures selected from range crystallization corresponding to α’ α form poly(L-lactide), i.e., 40, 70, 90, 120 °C, order verify sinterability set as sintering window (SW). Based differential scanning calorimetry measurements, SWs evaluated consideration existence reorganization crystal polymorphs. results indicated that influenced availability depending presence. postulate need an individual approach powders determining SW free any events. also characterized other core powder characteristics, such residual solvent content, morphology, particle size distribution, flowability, conductivity, key properties successful laser sintering. close spheres, was 100 µm. decreased increase annealing temperature. conductivities 0.073 0.064 W/mK PLA PLLA microspheres, respectively, this depended spherical shape microspheres. wide angle X-ray diffraction (WAXD) studies proved caused slight crystallinity degree clear