Hydrophilic and antimicrobial properties of acrylic acid and chitosan bigrafted polypropylene melt-blown nonwoven membrane immobilized with silver nanoparticles

The polypropylene melt-blown nonwoven membrane (PPM) is widely used in healthcare; however, the highly hydrophobic nature of the PPM readily adsorbs proteins and polysaccharides, which are conducive to bacteria being retained in the network, resulting in biofouling. Therefore, to improve the hydrophilic and antimicrobial properties of PPM, acrylic acid (AA) was first graft-polymerized on PPM (PPM- g-AA) by ultraviolet (UV)-induced photo-grafting polymerization. Chitosan (CS) was then covalently grafted onto PPM- g-AA to obtain the bigrafted PPM (PPM- g-AA- g-CS). Finally, silver (Ag) nanoparticles were immobilized onto PPM- g-AA- g-CS to create the hydrophilic and antibacterial PPM. The surface chemical composition and morphology of the samples were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The hydrophilic and antimicrobial properties of the modified PPM were assessed using static water contact angle measurements, wetting time, and bacteria colony-counting assays. The results show that PPM- g-AA- g-CS with immobilized Ag nanoparticles has excellent antibacterial and hydrophilic properties.