In this study, we fabricated para-aramid flexible angle-ply-laminated hybrid composites based on weft-knitted reinforcements. Here, four kinds of weft-knitted reinforcements with rib, interlock, punto di roma, and two-thread fleecy were prepared using para-aramid spun yarn. They were then compounded with silicone rubber and waterborne polyurethane–acrylate using the coating method. The layers were angle-plied to produce stab-resistant, weft-knitting-reinforced, flexible laminated hybrid composites. Tensile and tearing strengths of the para-aramid-knitted reinforcements were investigated. Relevant response analyses were chosen to evaluate the influence of three independent variables, including weft-knitted structures, matrix types, and ply orientations. The results showed that the mechanical properties of the composites were dependent on weft-knitted structures and matrix types. The fabric with high strength and the degree in approximate isotropy of stress in all composites was most suited for the reinforcement of the flexible stab-resistant composite. The optimum design with the best stab-resistant property was punto di roma/waterborne polyurethane–acrylate with a ply orientation angle of [0°/0°/0°/0°]. The interlaminar adhesion of flexible stab-resistant composite based on waterborne polyurethane–acrylate can be improved by increasing the surface roughness of fabric structure or modifying its surface.

中文翻译：

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抗刺角层柔性复合材料的力学性能表征

在这项研究中，我们制造了基于纬编增强材料的对位芳纶柔性角层层压混合复合材料。在这里，使用对位芳纶短纤纱制备了四种具有罗纹、互锁、punto di roma 和两线起绒的纬编增强材料。然后使用涂层方法将它们与硅橡胶和水性聚氨酯-丙烯酸酯混合。这些层被斜叠以生产抗刺伤、纬编增强、柔性层压混合复合材料。研究了对位芳纶针织增强材料的拉伸强度和撕裂强度。选择相关响应分析来评估三个独立变量的影响，包括纬编结构、矩阵类型和层片方向。结果表明，复合材料的力学性能取决于纬编结构和基体类型。在所有复合材料中，强度高且应力近似各向同性程度的织物最适合用于柔性防刺复合材料的增强。具有最佳抗刺性能的优化设计是铺层取向角 [0°/0°/0°/0°] 的 punto di roma/水性聚氨酯-丙烯酸酯。基于水性聚氨酯-丙烯酸酯的柔性防刺复合材料的层间附着力可以通过增加织物结构的表面粗糙度或对其表面进行改性来提高。在所有复合材料中，强度高且应力近似各向同性程度的织物最适合用于柔性防刺复合材料的增强。具有最佳抗刺性能的优化设计是铺层取向角 [0°/0°/0°/0°] 的 punto di roma/水性聚氨酯-丙烯酸酯。基于水性聚氨酯-丙烯酸酯的柔性防刺复合材料的层间附着力可以通过增加织物结构的表面粗糙度或对其表面进行改性来提高。在所有复合材料中，强度高且应力近似各向同性程度的织物最适合用于柔性防刺复合材料的增强。具有最佳抗刺性能的优化设计是铺层取向角 [0°/0°/0°/0°] 的 punto di roma/水性聚氨酯-丙烯酸酯。基于水性聚氨酯-丙烯酸酯的柔性防刺复合材料的层间附着力可以通过增加织物结构的表面粗糙度或对其表面进行改性来提高。