Graft Polymerization of Acrylic Acid on a Polytetrafluoroethylene Panel by an Inductively Coupled Plasma

Abstract

Surface modification on a polytetrafluoroethylene (PTFE) panel was performed with sequential nitrogen plasma treatments and surface-initiated polymerization. By introducing COO– groups to the surface of the PTFE panel through grafting polymerization of acrylic acid (AA), a transparent poly (acrylic acid) (PAA) membrane was achieved from acrylic acid solution. Grafting polymerization initiating from the active groups was achieved on the PTFE panel surface after the nitrogen plasma treatment. Utilizing the acrylic acid as monomers, with COO– groups as cross link sites to form reticulation structure, a transparent poly (acrylic acid) membrane with arborescent macromolecular structure was formed on the PTFE panel surface. Analysis methods, such as fourier transform infrared spectroscopy (FTIR), microscopy and X-ray photoelectron spectroscopy (XPS), were utilized to characterize the structures of the macromolecule membrane on the PTFE panel surface. A contact angle measurement was performed to characterize the modified PTFE panels. The surface hydrophilicities of modified PTFE panels were significantly enhanced after the plasma treatment. It was shown that the grafting rate is related to the treating time and the power of plasma.