Production of high-performance multi-layer fine-fibrous filter material by application of material extrusion–based additive manufacturing

This study addresses a new approach to production of multi-layer fine-fibrous filter material by application of material extrusion–based additive manufacturing (MEB-AM). By the example of polypropylene/copolyamide (PP/CPA), the ability of a fibrous composite structure formation in the initial strands is demonstrated. It is shown that a change in the size of filter grid cells and the extrusion pressure allows control of the diameter of PP fibrils. It is found that multi-layered composite films formed by MEB-AM of the strands retain the structure inherent in the strands. A polypropylene precision filter material has been produced by extraction of a matrix polymer from composite films. The achieved filter retention is about 100% (for the particles of 0.3–1.0 μm in size).