The metamaterials with negative Poisson’s ratio are called auxetic materials, which as a branch of metamaterials has drawn a lot of attention in many areas. Existing auxetic knitting textiles combine flexibility and auxeticity, however the loose structure has been a main disadvantage for its application. In this study, we fabricated Miura origami structure fabrics by weaving technology in order to acquire more stable auxetic textiles. The results show that using the combination of fabric structure type and elastic yarns, an origami structure can be realized in a jacquard loom. In the Miura origami structure, the crease pattern can be separated into three parts, unfolding areas, convex areas, and concave areas. One warp system and two weft systems are compounded together, in which a weft backed weave is used to get elastic floats in the convex and concave areas, and to make the fabrics bend to the concave side. The physical map showed that the fabrics had a clear Miura origami structure and the unfolding areas were flat and even. On the basis of the designed geometric pattern, weft backed weaves can be used to construct different folded areas, spandex wrapped PET (Polyester) and inelastic PET are selected as two weft systems for weaving. Meanwhile, the Miura origami fabrics exhibit distinct in-plane negative Poisson’s ratio and out-of-plane positive Poisson’s ratio. Apart from the Miura origami structure, other origami and paper-cut structures can be realized using this method, and these special auxetic textiles have potential in protective cloths, ornamented textiles, wearable devices, and flexible sensors.

In order to study the deformation behavior of double arrowhead (DAH) auxetic metamaterials under different forces with different directions as well as the effects of the geometry parameters on the Poisson's ratio, this paper assembled an advanced researching method by combining the industrial design of SolidWorks software, the finite element analysis of Abaqus software and three-dimensional printed technology. Results show that the DAH structure expanded in the direction perpendicular to the force first and contracted with the strain increasing when it was pulled by the uniaxial force, no matter which direction the force is applied. Besides, the auxetic effect of the DAH structure under the tensile force in the X direction is longer than that under the tensile force in the Y direction. It is more resistant to compression when the DAH structure is subjected to transverse tensile forces than when it is subjected to longitudinal tensile forces. The angle of the V-shaped short truss has a significant impact on the negative Poisson's ratio of the DAH structure, while the angle of the V-shaped long truss angle has little influence on its auxetic performance. Specifically, the smaller the angles, the better the auxetic effect.

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A novel eco-friendly and durable superhydrophobic and flame-retardant cotton fabric with fluorine-free, halogen-free was prepared via step-by-step dip-coating and spraying technology. At first, common cotton fabric was impregnated in the flame-retardant ethoxysilane-terminated phosphate polyurethane. Afterwards, methanol mixture containing silica nanoparticles, methyl triethoxysilane, and dihydroxy-terminated polydimethylsiloxane was sprayed on the surface of the cotton fabric. Finally, a flame-retardant cotton fabric with micro-nano rough surface and low surface energy was formed. The resulting superhydrophobic and flame-retardant cotton fabric exhibited superamphiphobicity with the contact angle and sliding angle of 160° and 6°, respectively, while flame retardancy with limited oxygen index of 28.1%. and flame self-extinguishing. Furthermore, this superhydrophobic and flame-retardant cotton fabric showed robust superhydrophobicity and flame-retardancy after undergoing 1000 cycles of abrasion, 60 min of ultrasonic washing and 50 standard machine washing cycles, in sequence, indicating its potential as a multifunctional protective textile fabric. Additionally, the method proposed in this study can effectively solve durability and environmental problems currently faced by the coated fabric with superhydrophobicity and flame-retardancy.

Spacer fabrics have been developed into a variety of special textile mattress products due to their outstanding pressure distribution performance. It may be that the contacting area of spacer fabrics can be expanded under spherical compression. The total compression force and distance curve is currently used to test the compression of spacer fabrics; however, there are few detailed reports about expanding the contacting area under the spherical intender. Therefore, this paper developed a test method for the contacting area between the spacer fabric and the spherical indenter under spherical compression. The spherical indenter was specially designed by using serial resistors method. The contacting area was easily obtained by detecting the resistance change through 12 resistors pasted on the surface of the spherical indenter and calculating the surface of the spherical indenter under dynamic movement. This method can be used to effectively characterize the pressure-relief property of textile soft materials in pad materials.