Combining Solution-Blowing and Melt-Blowing Techniques to Produce an Efficient Non-Woven Filter

New substances and particles appearing in the environment following technological development pose new challenges for separation methods. Moreover, the growing amount of waste also forces us to look for environmentally friendly solutions. One way to create filtration structures with the desired properties is to combine known techniques, thanks to which the advantages of one technique complement the deficiencies and disadvantages of another. Combining the melt-blowing and solution-blowing processes seems to be promising. Fibres created from melt-blowing will provide mechanical strength, while solution-blowing will allow the introduction of nanofibres into the structure with unique filtration and functional properties. Both methods enable working with biodegradable polymers, so the resulting filter can also be environmentally friendly after operation. Our research aimed to check whether combining two fibre production techniques (melt-blown and solution-blowing) is possible and how the joining method will affect the final product. We created a multilayer structure by placing a layer of solution-blowing nanofibres between melt-blown layers, and a mixed structure by simultaneous melt-blowing and solution-blowing. The created multilayer structure was characterised by high filtration efficiency and high-pressure drop. In contrast, the mixed structure achieved a high-quality factor and high mass of deposited droplets per 1 J of energy used for work.