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A microclimate with ventilation and proper wettability near the wound is vital for wound healing. In the case of pressure or absorption of large amounts of wound exudate, maintaining air circulation around the wound is currently a challenge for wound dressings. In this study, a novel self-pumping dressing (FAED) with multiple liquid transport channels is designed by combining a 3D spacer fabric, sodium alginate aerogel, and electrospun membrane. This unique structural design allows FAED to unidirectionally rapidly remove excess biofluid from the wound and transfer it through a special liquid transport channel to a liquid storage layer with a high absorption ratio. Importantly, the air circulation layer of FAED composed of liquid transport channels and spacer yarns provides excellent air permeability in both the horizontal (12.3 L min −1 ) and vertical (272.02 mm s −1 ) directions. Additionally, a lower compression modulus (0.14 MPa) and higher compression strength (0.15 MPa) enable the novel dressing to adapt to body contours and provide good supporting performance, as compared to foam dressings. Combined with its high biocompatibility, this unique dressing has significant potential for wound treatment and intensive care.

In this study, a new type ternary composite, called warp-knitted spacer fabric reinforced syntactic foam (WKSF-SF), with the advantages of high mechanical properties and a lower density, was proposed. Then, a meso-mechanics theoretical model based on the Eshelby–Mori–Tanaka equivalent inclusion method, average stress method and composite hybrid theory was established to predict the compression modulus of WKSF-SF. In order to verify the validity of this model, compression modulus values of theoretical simulations were compared with the quasi-static compression experiment results. The results showed that the addition of suitable WKSF produces at least 15% improvement in the compressive modulus of WKSF-SF compared with neat syntactic foam (NSF). Meanwhile, the theoretical model can effectively simulate the values and variation tendency of the compression modulus for different WKSF-SF samples, and is especially suitable for the samples with smaller wall thickness or a moderate volume fraction of microballoons (the deviations is less than 5%). The study of the meso-mechanical properties of WKSF-SF will help to increase understanding of the compression properties of this new type composite deeply. It is expected that WKSF-SF can be used in aerospace, marine, transportation, construction, and other fields.

Many pressure wound protection products, such as pressure redistribution supports and exuding wound dressings, are made of polyurethane sponge. However, polyurethane sponge does not possess a desirable combination of air permeability, moisture management and mechanical properties required by pressure redistribution supports and exuding wound dressings. This study explores the optimization of a 3D warp-knitted spacer fabric (WKSF) structure for pressure ulcer protection. The influence of construction and material parameters on the compression performance and air permeability of WKSFs was investigated by numerical simulation and then validated with experiments. The moisture transport and wetting properties of WKSFs were characterized by a moisture management tester. The numerical simulation and experimental results indicate that the WKSF structure can be tuned to achieve compressional properties, air permeability, and moisture management performance that are more suitable for pressure ulcer protection than polyurethane sponge. WKSFs constructed with a low-density surface layer, coarser spacer yarns, and larger spacer yarn inclination-angle are more suitable for pressure redistribution support surfaces, while WKSFs constructed with dense surface layers and coarse spacer yarn can better meet the performance requirements of exuding wound dressings.