State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, People's Republic of China.
Biofabrication. 2013 Jun;5(2):025005. doi: 10.1088/1758-5082/5/2/025005. Epub 2013 Mar 5.
To improve the mechanical properties of a scaffold fabricated via selective laser sintering (SLS), a small amount (0.5-3 wt%) of poly-l-lactic acid (PLLA) is added to the β-tricalcium phosphate (β-TCP) powder. The fracture toughness of the scaffold prepared with the mixture powder containing 1 wt% PLLA increases by 18.18% and the compressive strength increases by 4.45% compared to the scaffold prepared from the β-TCP powder. The strengthening and toughening is related to the enhancement of β-TCP sintering characteristics via introducing a transient liquid phase in SLS. Moreover, the microcracks caused by the volume expansion due to the β-α phase transformation of TCP are reduced because of the PLLA inhibition function on the phase transformation. However, PLLA additive above 1 wt% would lead to a PLLA residue which will decrease the mechanical properties. The experimental results show that PLLA is an effective sintering aid to improve the mechanical properties of a TCP scaffold.
为了提高选择性激光烧结（SLS）制备的支架的力学性能，在 β-磷酸三钙（β-TCP）粉末中添加少量（0.5-3wt%）聚左旋乳酸（PLLA）。与由β-TCP 粉末制备的支架相比，含有 1wt% PLLA 的混合粉末制备的支架的断裂韧性提高了 18.18%，抗压强度提高了 4.45%。增强和增韧与通过在 SLS 中引入瞬态液相来增强β-TCP 的烧结特性有关。此外，由于 PLLA 对相转变的抑制作用，TCP 的β-α 相转变引起的体积膨胀产生的微裂纹减少。然而，超过 1wt%的 PLLA 添加剂会导致 PLLA 残留，从而降低机械性能。实验结果表明，PLLA 是一种有效的烧结助剂，可提高 TCP 支架的力学性能。
