New hydrophilic polypropylene membranes; fabrication and evaluation

This article discusses a new method to prepare polypropylene membrane that has hydrophilic surfaces and asymmetric porous structure. This membrane is based on a newly developed hydroxylated polypropylene (PP-OH), which has a "brushlike" microstructure, high molecular weight, high melting point, and relatively high concentration of hydroxy groups. Under the leaching process conditions, various asymmetric hydrophilic PP/PP-OH membranes are prepared with controllable pore structures. The PP-OH polymer becomes the surface modifier of asymmetric PP membrane with flexible functional groups located on the membrane surfaces, including pore surfaces. This new hydrophilic PP PP-OH membrane is useful in ultrafiltration, not only offering good selectivity and flux but also showing excellence in antifouling property.