| Abstract: | Poly‐l‐lactic acid (PLLA) is considered as a potential bone scaffold material because of good biocompatibility and bioabsorbability, whereas too slow degradation rate limits its application. In this study, montmorillonite (MMT) was introduced into PLLA scaffolds fabricated via selective laser sintering to accelerate degradation by reducing crystallinity. To be specific, MMT was a layered silicate with large surface area and aspect ratio, which provided nucleation site for the crystallization of PLLA molecular chain along their surface during the sintering process. As the surface of MMT plate was randomly oriented in the matrix, the growth direction of crystallite was also random, which interrupted the orderly crystallization, thus decreasing the overall crystallinity of PLLA. As a result, the crystallinity of PLLA scaffolds was decreased from 32.3% to 27.4% when introducing 4.5% MMT. Accordingly, weight loss was increased from 0.83% to 7.25% after immersing for 4 weeks. Besides, the tensile strength and modulus of the scaffolds increased by 44.1% and 66.9% because of the change of fracture mode from brittle fracture to ductile fracture. In addition, the scaffolds also demonstrated good hydrophilic property and cell compatibility. |
