Powder Technology, Vol.354, 289-300, 2019
Evaluating porous polylactide-co-glycolide/bioactive glass composite microsphere powders for laser sintering of scaffolds
While laser sintering (LS) processes are typically optimised towards denser powder beds, our approach is different as we investigate the use of non-dense powder beds made of porous composite powder materials of polylactide-co-glycolide (PLGA) and bioactive glass (BG) 45S5. Powders were produced via solid-in-oil-in-water emulsion with modified BG as porogen and changing PLGA:BG ratios with up to 50 wt% of BG. Characterisation was done using scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), thermal gravimetric analysis (TG), powder packing and flow, particle-size distribution (PSD) and X-ray tomography. The microparticles showed varying degrees of sphericity, porosity and specific surface area (SSA), while the BG porogen could be incorporated into or onto the foamed polymer. Powders were used for LS and gave parts with an overall porosity of similar to 75%. Our special approach might be interesting for multi-material LS for real biomimetic scaffolds with tailored hierarchical pore structures. (C) 2019 Elsevier B.V. All rights reserved.
Keywords:Porous microspheres;Laser sintering;Tissue engineering scaffolds;Biomimetic scaffolds;PLGA;Bioactive glass