George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA.
Acta Biomater. 2010 Jul;6(7):2467-76. doi: 10.1016/j.actbio.2010.02.002. Epub 2010 Feb 8.
This article reports on the experimental determination and finite element modeling of tensile and compressive mechanical properties of solid polycaprolactone (PCL) and of porous PCL scaffolds with one-dimensional, two-dimensional and three-dimensional orthogonal, periodic porous architectures produced by selective laser sintering (SLS). PCL scaffolds were built using optimum processing parameters, ensuring scaffolds with nearly full density (>95%) in the designed solid regions and with excellent geometric and dimensional control (within 3-8% of design). The tensile strength of bulk PCL ranged from 10.5 to 16.1 MPa, its modulus ranged from 343.9 to 364.3 MPa, and the tensile yield strength ranged from 8.2 to 10.1 MPa. These values are consistent with reported literature values for PCL processed through various manufacturing methods. Across porosity ranged from 56.87% to 83.3%, the tensile strength ranged from 4.5 to 1.1 MPa, the tensile modulus ranged from 140.5 to 35.5 MPa, and the yield strength ranged from 3.2 to 0.76 MPa. The compressive strength of bulk PCL was 38.7 MPa, the compressive modulus ranged from 297.8 to 317.1 MPa, and the compressive yield strength ranged from 10.3 to 12.5 MPa. Across porosity ranged from 51.1% to 80.9%, the compressive strength ranged from 10.0 to 0.6 MPa, the compressive modulus ranged from 14.9 to 12.1 MPa, and the compressive yield strength ranged from 4.25 to 0.42 MPa. These values, while being in the lower range of reported values for trabecular bone, are the highest reported for PCL scaffolds produced by SLS and are among the highest reported for similar PCL scaffolds produced through other layered manufacturing techniques. Finite element analysis showed good agreement between experimental and computed effective tensile and compressive moduli. Thus, the construction of bone tissue engineering scaffolds endowed with oriented porous architectures and with predictable mechanical properties through SLS is demonstrated.
本文报告了通过选择性激光烧结（SLS）制造的具有一维、二维和三维正交周期性多孔结构的固体聚己内酯（PCL）和多孔 PCL 支架的拉伸和压缩力学性能的实验测定和有限元建模。使用最佳的加工参数制造 PCL 支架，确保设计的实心区域中的支架具有几乎完全的密度（>95%）和出色的几何和尺寸控制（在设计的 3-8%范围内）。大块 PCL 的拉伸强度范围为 10.5 至 16.1 MPa，其模量范围为 343.9 至 364.3 MPa，拉伸屈服强度范围为 8.2 至 10.1 MPa。这些值与通过各种制造方法加工的 PCL 的报告文献值一致。多孔率范围为 56.87%至 83.3%时，拉伸强度范围为 4.5 至 1.1 MPa，拉伸模量范围为 140.5 至 35.5 MPa，屈服强度范围为 3.2 至 0.76 MPa。大块 PCL 的压缩强度为 38.7 MPa，压缩模量范围为 297.8 至 317.1 MPa，压缩屈服强度范围为 10.3 至 12.5 MPa。多孔率范围为 51.1%至 80.9%时，压缩强度范围为 10.0 至 0.6 MPa，压缩模量范围为 14.9 至 12.1 MPa，压缩屈服强度范围为 4.25 至 0.42 MPa。虽然这些值处于报告的小梁骨值的较低范围，但它们是通过 SLS 制造的 PCL 支架中报告的最高值，并且与通过其他层制造技术制造的类似 PCL 支架的报告值相比处于较高水平。有限元分析表明，实验和计算的有效拉伸和压缩模量之间具有良好的一致性。因此，通过 SLS 制造具有定向多孔结构和可预测机械性能的骨组织工程支架的构建得到了证明。
