Reinforcing hydrogels with micro-fibre scaffolds obtained by a Melt-Electrospinning Writing (MEW) process has demonstrated great promise for developing tissue engineered (TE) constructs with mechanical properties compatible to native tissues. However, the mechanical performance and reinforcement mechanism of the micro-fibre reinforced hydrogels is not yet fully understood. In this study, FE models, implementing material properties measured experimentally, were used to explore the reinforcement mechanism of fibre-hydrogel composites. First, a continuum FE model based on idealized scaffold geometry was used to capture reinforcement effects related to the suppression of lateral gel expansion by the scaffold, while a second micro-FE model based on micro-CT images of the real construct geometry during compaction captured the effects of load transfer through the scaffold interconnections. Results demonstrate that the reinforcement mechanism at higher scaffold volume fractions was dominated by the load carrying-ability of the fibre scaffold interconnections, which was much higher than expected based on testing scaffolds alone because the hydrogel provides resistance against buckling of the scaffold. We propose that the theoretical understanding presented in this work will assist the design of more effective composite constructs with potential applications in a wide range of TE conditions.

中文翻译：

---

三维印刷的微纤维支架增强的软水凝胶的机械性能。

用通过熔体静电纺丝（MEW）工艺获得的微纤维支架来增强水凝胶已显示出开发具有与天然组织相容的机械性能的组织工程（TE）构建体的巨大希望。然而，尚未充分了解微纤维增强的水凝胶的机械性能和增强机理。在这项研究中，有限元模型，实现了通过实验测量的材料性能，被用来探索纤维-水凝胶复合材料的增强机理。首先，使用基于理想支架几何形状的连续有限元模型来捕获与支架抑制侧向凝胶膨胀有关的增强效应，而第二个基于实际构造几何结构的微CT图像的微FE模型则捕获了通过脚手架互连传递的载荷的影响。结果表明，在较高的脚手架体积分数下，增强机理主要由纤维脚手架互连的承载能力决定，该能力远高于单独测试脚手架时的预期，因为水凝胶提供了抵抗脚手架屈曲的能力。我们建议这项工作中提出的理论理解将有助于设计更有效的复合结构，并在广泛的TE条件下具有潜在的应用。结果表明，在较高的脚手架体积分数下，增强机理主要由纤维脚手架互连的承载能力决定，该能力远高于单独测试脚手架时的预期，因为水凝胶提供了抵抗脚手架屈曲的能力。我们建议这项工作中提出的理论理解将有助于设计更有效的复合结构，并在广泛的TE条件下具有潜在的应用。结果表明，在较高的脚手架体积分数下，增强机理主要由纤维脚手架互连的承载能力决定，该能力远高于单独测试脚手架时的预期，因为水凝胶提供了抵抗脚手架屈曲的能力。我们建议这项工作中提出的理论理解将有助于设计更有效的复合结构，并在广泛的TE条件下具有潜在的应用。