Electrospinning Equipment: Easily prepare environmentally friendly and mechanically strong transparent, waterproof and breathable fiber membranes

Background

Functional fiber membranes that combine optical transparency, waterproofness and breathability have wide application demands in many fields, such as medical protection, electronic skin, greenhouse covering materials, and outdoor equipment. However, the development of such materials still faces many challenges, including complex manufacturing processes, difficult performance balance, and environmental and health issues. Harmful solvents and fluorinated polymers commonly used in traditional manufacturing processes are not only environmentally unfriendly, but may also cause health risks.

Research content and results

The research team of Professor Huang Gang, Associate Professor Zhao Jing, Professor Wang Xianfeng and Associate Professor Feng Qi of Wuyi University published in the Chemical Engineering Journal proposed an environmentally friendly and efficient new method for manufacturing transparent, waterproof and breathable membranes (TWBMs). This method combines electrospinning technology and thermal curing technology of fluorine-free paraffin emulsion coating. The specific steps are as follows:

Electrospinning preparation of fiber membrane: Using ethanol as a green solvent, ethanol-soluble polyamide (EPA) and water-based polymer isocyanate (API) are dissolved to prepare a spinning solution, and EPA/API fiber membranes are obtained by electrospinning technology. This fiber membrane has high porosity and good air permeability, but its transparency is low in the initial state.

Fluorine-free paraffin wax emulsion coating treatment: The prepared EPA/API fiber membrane is immersed in an aqueous, fluorine-free paraffin wax emulsion (PWE) to cover the fiber surface with a PWE coating. This step gives the fiber membrane excellent hydrophobicity, while reducing the pore size and enhancing the bonding structure between fibers.

Heat curing treatment: Through an optimized heat curing process, the porous structure and thickness of the fiber membrane are precisely controlled to achieve high transparency while retaining the microporous structure to ensure air permeability. The heat curing process not only improves the optical properties of the membrane, but also significantly enhances its mechanical strength.

Performance

Optical transparency: The final TWBMs membrane has a high transmittance of 90%.

Waterproof performance: The membrane exhibits excellent water resistance of 111.4 kPa, which is much higher than commercially available transparent materials.

Air permeability: The water vapor permeability reaches 5.3 kg/m²·d, which meets the needs of practical applications.

Mechanical properties: The tensile strength of the membrane is 21.2 MPa, and the elongation at break is 568%, showing good flexibility and mechanical strength.

Connection with electrospinning technology

Preparation of high-performance fiber membranes:Electrospinning can prepare fiber membranes with uniform diameter and high porosity, providing an ideal substrate for subsequent coating treatment.

Application of green solvents: Using ethanol as a solvent avoids harmful solvents used in traditional processes and meets environmental protection requirements.

Multifunctional integration: Electrospinning technology combines fluorine-free paraffin emulsion coating and thermal curing process to achieve the optimization of waterproof, breathable and transparent properties of fiber membranes.

Scalability: The scalability of electrospinning technology makes it suitable for large-scale production, providing the possibility for the commercial application of TWBMs.

Future prospects

This study not only proposes an environmentally friendly and efficient method for preparing TWBMs, but also provides new ideas for the design and application of multifunctional fiber membranes. In the future, with the further development of electrospinning technology, TWBMs are expected to be applied in more fields, such as flexible electronic devices, smart wearables and medical protection. By optimizing the electrospinning process and coating technology, the performance of TWBMs is expected to be further improved, providing a valuable reference for the development of the next generation of high-performance fiber membranes.

Electrospinning Nanofibers Article Source:

https://doi.org/10.1016/j.cej.2025.159222