Improvement Of The Hydrophilization Of Polypropylene Microporous Membranes By Surface Modifications

Trace amounts of irrigation technology is a new methods economize waterresource. The core of the new technology is control head that supply water to soilslowly and continuously. In an attempt to improve the hydrophilic modification andanti-pollution of polypropylene microporous membrane， membrane surfacemodification is a good job. Polypropylene microporous membrane was modificatedby different methods because of chemical corrosion and durable.Main points are as follows：1. Surface modification of polypropylene microporous membrane was performedby cross-linking between polyvinyl alcohol and glutaraldehyde. Impacts of reactiontime， concentration of glutaric dialdehyde and polyvinyl alcohol on theimmobilization degree. The structures of the polypropylene microporous membranewas characterized by attenuated total reflectance-Fourier transform infrared. Theresults show that the immobilization degree is improved with the increasing ofreaction time，temperature and concentration of polyvinyl alcohol. The microporousmembrane has excellent hydrophilic modification and anti-fouling performance.2. Surface modification by adsorption Tween80was accomplished onpolypropylene microporous membrane. The absorption of Tween80occurred inmembrane pores at low concentration, and on the membrane surface at highadsorption amount. Adsorption amount is raised with the increase of Tween80concentration，the surface hydrophilic and water flux are increased.3. Acrylicamide was grafted onto the surface of polypropylene microporousmembrane by UV grafting polymerization. The effects of reaction time, theconcentration of benzophenone and acrylicamide on the degree of grafting werestudied. The results show that degree of grafting is raised with the increasing ofreaction time. When the reaction time is more than30minutes, the grafting degree ofacrylicamide remain the same. With increasing of the concentration of benzophenoneand acrylicamide, polypropylene microporous membrane’s grafting degree raised with excellent hydrophilic and anti-fouling performance. The optimum irradiation time is30min, the optimum acrylicamide concentration1.2wt%and benzophenoneconcentration1.0wt%.