Structural and Performance Effects of Self‐Assembled Composite Antibacterial Additives on <scp>PP</scp> Melt‐Blown Nonwovens Based on Melt Reaction Extrusion

ABSTRACT In this study, a hybrid microsphere structure with a polyhexamethyleneguanidine hydrochloride (PHMG) core and a nano‐zinc oxide (Nano‐ZnO) antibacterial additive shell was designed through the reaction extrusion in polypropylene (PP). The realization of this structure enabled the successful resolution of the agglomeration problem of Nano‐ZnO and achieved a synergistic antibacterial effect between Nano‐ZnO and PHMG. Special attention was paid to the interaction between Nano‐ZnO and PHMG through the organic–inorganic hybridization. In addition, the nonwoven materials with different Nano‐ZnO and PHMG contents were prepared via a melt‐blown technique in PP, and their antibacterial properties were evaluated as well. Based on the findings, the synergistic antimicrobial mechanism of Nano‐ZnO/PHMG structures was established. The results showed that the addition of 2% Nano‐ZnO and 1% PHMG in PP (PP/2%ZnO/1%PHMG) allowed for the production of a melt‐blown nonwoven material with an antibacterial efficiency of 99.99% against Staphylococcus aureus and Escherichia coli . Besides that, the material exhibited the outstanding performance and durability (the breaking strength of 2.43 N, the air permeability of 537 mm/s, the filtration efficiency of 97.25%, and the filtration resistance of 28.38 Pa).