Hollow structured materials have exhibited potential applications in numerous areas due to their unique properties. These materials have been extensively explored in the textile industry for their excellent mechanical properties. For instance, monofilaments with outstanding compression property are highly desirable in developing warp-knitted spacer fabrics with a wide range of applications. Specifically, bamboo has a hollow structure capable of withstanding large loads. Bamboo canes ensure better compression performance while the knots, on the other hand, ensure adequate stability. Inspired by nature, researchers have pursued the development of textiles i.e. warp-knitted fabrics for a wide range of applications. Unfortunately, it is difficult to produce bamboo structure hollow monofilaments using the currently available manufacturing methods.
Recently, 3D printing has been identified as an alternative method for manufacturing hollow fibers. To this note, Professor Pibo Ma and Xiaohui Zhang (Ph.D. Student) from Jiangnan University in collaboration with Dr. Xin Wang from RMIT University and Dr. Yantao Gao from Shanghai Institute of Applied Physics explored the compression properties of the bamboo-structure monofilaments with precise and diversified structures, fabricated by fused deposition modeling 3D printing technology. Polyester was used as a feeding wire for the rapid deposition of the hollow monofilaments. Eventually, the bamboo structure hollow monofilaments were compared with other filaments of the same weight and stricture. The research work is currently published in the Composite Structures journal.
The bamboo-structure hollow monofilaments exhibited better compression properties and stress distribution compared with other filaments. Consequently, warp-knitted spacer fabrics fabricated by bamboo structure hollow monofilament undertook more load per unit mass than its solid and continuous hollow monofilaments counterparts. Additionally, the load per unit mass was observed to increase with an increase in the hollow part. Furthermore, finite element analysis revealed that the compression characteristics of the bamboo-structured monofilaments were consistent with that of spacer monofilaments in warp-knitted spacer fabrics. This demonstrated the three stages involved in the compressions process: pure compression stage, bending stage and buckling bending stage.
It was worth noting that for spacer fabrics under compression loading, the compression process is defined in terms of the bending and deformation process of spacer monofilaments. Research has shown that the compression properties vary depending on the internal structures of the spacer monofilaments. This shows the importance of exploring the compression behavior of monofilaments with new internal structures such as the hollow bamboo structure, which has exhibited great potential of reducing the weight of warp-knitted spacer fabric by enhancing its compression property.
The authors are the first to successfully fabricate a novel bamboo-structure hollow monofilament through 3D printing technology. This structure exhibited great potential of enhancing the compression property of the warp-knitted fabric while at the same time reducing its weight. The bamboo-structure monofilaments will, therefore, provide more insights for effective design and fabrication of warp-knitted spacer monofilaments. This, according to Professor Pibo Ma, will provide new opportunities for the exploration of new applications.
Zhang, X., Wang, X., Gao, Y., & Ma, P. (2019). Fabrication of bamboo-structure hollow polyester monofilaments for extraordinary compression properties. Composite Structures, 230, 111423.