Recent advances in hydrophilic modification of PVDF ultrafiltration membranes – a review: part I

With the increasing importance of water treatment and wastewater recovery, the use of membrane processes, to obtain drinking and tap water, is spreading rapidly worldwide. Poly(vinylidene fluoride) (PVDF) has been used extensively in ultrafiltration (UF) membranes because of its outstanding properties, such as high mechanical strength, thermal stability and chemical resistance. Nevertheless, membranes made from PVDF may be susceptible to biofouling because of the material's strong hydrophobicity. This review article focuses on recent advances in hydrophilic modification methods that are applied to PVDF UF membranes in order to enhance antifouling performance, mechanical strength and chemical resistance. The first instalment, which appears here, provides details of the types of membrane fouling and fouling mechanisms, and modification methods such as surface coating and surface grafting that are used to increase the hydrophilicity of PVDF UF membranes.