New achievements of Donghua University: moisture absorption and quick drying function based on biomimetic porous Murray membrane

In recent years, the rapid development of clothing, medical and health materials such as high-end sportswear, field uniforms, diapers, wound dressings has led to an increasing demand for moisture-absorbing and quick-drying textile materials with a single-guide wet function. The single-guide wet fabric delivers a fast drying effect in hot and humid environments by delivering sweat and moisture from the body to the external environment, providing a comfortable micro-environment for the body. However, the preparation process of the existing single-guide wet fabric is complicated, and at the same time, since the specific surface area of ​​the conventional fiber is small, the derived moisture cannot be quickly evaporated, resulting in poor wearing comfort.

In nature, transpiration in ductal plants has two characteristics: self-driven reverse gravity oriented water transport and ultrafast evaporation. This is because they have a tree-like fractal bifurcation network structure that conforms to Murray's law, and optimizes the transport capacity of moisture in multi-level interconnected channels by minimizing transport resistance in multi-level cells. In addition, there are a large number of typical tree-like bifurcation structures in biological tissues, such as the animal's blood circulation system, respiratory system, neural network, etc. With the interdisciplinary intersection, such a tree-like bifurcation network is in the flow of microfluidics, for example. Control, urban water and electricity supply and other fields have been widely used, but due to the limitations of existing functional micro-nano fiber processing technology and materials, the application of bionic tree-like bifurcation network in the field of moisture absorption and quick-drying fabrics has not been explored.

Recently, the research group of Professor Ding Bin and Wang Xianfeng of Donghua University prepared a biomimetic porous Murray single-guide wet fiber membrane by constructing a dendritic network and surface energy gradient by electrospinning technology. Among them, the bionic tree-like multi-stage bifurcation network integrates multi-hole connected channels of macroporous-micron-submicron pores, has a multi-stage bifurcation structure similar to plant transpiration effect, and follows Murray's law to maximize the mass transport principle. The resulting biomimetic porous Murray membrane combines self-driven reversible gravity to guide water, rapid moisture absorption and desorption (water evaporation rate of up to 0.67 g / h, 2.1 times that of commercial Coolmax fabric) and excellent inner layer quick drying performance.

The work proposed in this work provides a new idea for constructing and improving the design and performance of the moisture-absorbing and quick-drying micro-nanofiber membrane material by constructing the bionic multi-stage pores and the surface energy gradient structure, and is expected to replace the existing commercial moisture-absorbing and quick-drying fabric to realize its Widely used in high-end functional clothing and medical materials. In the future work, the multi-stage wetting structure of micro-nano fiber membrane materials will be further optimized, and the directional transport mechanism of moisture in the pores of the fiber membrane will be revealed, and a high-performance moisture absorbing and quick-drying material can be obtained. The research results were published in "ACS Nano" under the title "Biomimetic Fibrous Murray Membranes with Ultrafast Water Transport and Evaporation for Smart Moisture-Wicking Fabrics".