Hydrophilic Modification Of Polypropylene Membrane By Maleic Anhydride Plasma Polymerization

Maleic anhydride is of particular interest for the synthesis of functional organic thin films because of the double bond and the reactive anhydride group. It can participate in a variety of chemical reactions occurring at the double bond by photochemical reactions, conventional polymerization, copolymerization, and graft polymerization. In this paper, a hydrophilic membrane was prepared by depositing maleic anhydride into a polypropylene microporous membrane by plasma technique, and the morphology of the deposited membranes was characterized. Different hydrolyzed conditions' effect on surface structure of membrane was investigated. Static contact angle of pure water on membrane was used to investigate the hydrophilicity of the deposited membrane and the relationship between the hydrophilicity and time. The flux of deposited membrane was tested.Firstly, maleic anhydride deposited polypropylene microporous membranes were prepared by low-temperature plasma polymerization with polypropylene membrane as a substrate. The structure and morphology of the deposited membranes were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analysis. The results of FT-IR analysis indicated that anhydride structure was not prone to be destroyed and a significantly higher relative amount of anhydride groups was enhanced with the increase of treating time in low treating power 10W. With the increase of treating power, the structure of anhydride was trend to be destroyed and formed higher relative carboxylic acid structure. The result of SEM analysis showed that there existed etching and polymerization phenomenon on the surface of membrane by maleic anhydride plasma polymerization. At low treating power, even though the treating time was increased, maleic anhydride film could be also formed on the surface of polypropylene membrane. which considered that maleic anhydride plasma polymerization mainly occurred on the surface of membrane. When the...