Plasma Grafting with Methyl Di-Ally Ammonium Salt to Impart Anti-Bacterial Properties to Polypropylene

Quaternary methyl di-ally ammonium salt (MDAA) was grafted on the swface of a polypropylene (PP) nonwoven using a low-temperature radio frequency discharge plasma. The graft ratio of MDAA to PP increased with the grafting temperature; at low grafting temperatures (30 or 60 degrees C), the graft ratio increased with the H2SO4 catalyst concentration, but at a high grafting temperature (80 degrees C), it was not affected, even without the use of an acid catalyst. The finished PP nonwoven exhibited excellent antibacterial activities toward Staphylococcus aureus, suggesting that plasma grafting is an effective method.