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Medical product contamination is a serious threat to patients’ health. However, designing medical covers that ensure Janus performance and outstanding abrasion resistance, mechanical performances has remained a great challenge. In this study, a novel Janus nonwoven fabric nonwoven fabric consists of a hydrophilic inner layer of polylactic acid (PLA)/lowmelting polylactic acid (LPLA) and a coated outer layer of hydrophobic thermoplastic polyurethane (TPU) is successfully fabricated. The subsequent PLA/LPLA-TPU textiles exhibits excellent protective performance of inner absorption. Moreover, the coating improves tensile strength and increases abrasion resistance. A mechanism of mechanical failure is further studied. This kind of nonwoven fabric is suggested to be a promising candidate for medical covers and health supplies.

With the significant advances in electronic products, materials with good flexibility, corrosion resistance, high electrical conductivity and minimal thickness are urgently needed. Herein, we demonstrate the biomimetic core–shell structure of lightweight, flexible, self-cleaning nanofiber films for high-performance electromagnetic interference (EMI) shielding by tuning the deposition of Ag nanoparticles (AgNPs). With a thickness of 0.06 mm, PAN@TiO2@AgNPs composite films (PTA films) exhibit an average EMI shielding effectiveness (SE) of 82.60 dB. After further processing with fluorine-containing molecules, the PTA-4 film becomes superhydrophobic and anticorrosive. After a hydrophobic treatment, composite films have average SE, specific SE (SSE) and SSE/t being 79.57 dB, 360.86 dB cm3 g−1, and 60143.33 dB cm2 g−1, respectively. In particular, conductive films that undergo UV radiation and bending cycles retain a stabilized electrical conductivity. This tuning bio-inspired fabrication method provides the films with UV-resistance, superhydrophobicity and EMI SE that fit the practical applications of wearable and flexible sensors.

Polyethylene terephthalate (PET) nonwoven fabrics, carbon fabrics (CF), and flexible polyurethane (PU) foams are made into novel sandwich composites using one-step molding. The flame retradance and mechanical properties of the sandwich composites are evaluated, examining the influences of the content of flame retardant agent (20, 30, 40, and 50 wt%) and areal density of PET panels (200, 300, and 400 g/m2). The test results show that the PET/CF/PU sandwich composites are rated flame retardant as V0 and do not generate melts. The failure mode of PET/CF/PU sandwich composites converts from overall fracture to layered fracture as a result of increasing the flame retardant agent. The tensile strength at break of PET/CF/PU sandwich composites with corresponding PET panels is 650 N for 200 g/m, 928 N for 300 g/m, and 1744 N for 400 g/m2, which are 42.63 %, 60.48 %, and 77.85 % greater than those of the PET/PU sandwich composites. Moreover, the bursting strength of PET/CF/PU sandwich composites with corresponding PET panels is 3322 N for 200 g/m2, 3869 N for 300 g/m2, and 4978 N for 400 g/m2, which are 195%, 180%, and 143% greater than those of the PET/PU sandwich composites.

In order to deeply explore the fiber characteristics influencing on stab resistance of shear thickening fluid (STF)- impregnated fabrics, two different weaving fabrics, ultra-high molecular weight polyethylene (UHMWPE) fabric and Kevlar fabrics are saturate the various concentrations and particle size of STFs. Result shows that, SiO2/PEG-200 blends demonstrate quick shear-thickening property, and the critical shear rate lowers to 1.2-45 s-1 with higher concentration of 75 nm SiO2. STF concentration and particle size significantly affect spike puncture resistance property, but the knife stab resistance mainly depends on fiber characteristics. Comparatively, STF-UHMWPE composite fabrics exhibit better knife stab resistance but weaker spike puncture resistance than STF-Kevlar fabrics. This study can provide an optimization for structure design of stab resistance armors in the future.