| 摘要 |
The present invention provides an isotropic, skinless, porous, polyvinylidene fluoride membrane having a KUF of at least about 15 psi, and preferably below about 50 psi, when tested using liquid pairs having an interfacial tension of about 4 dynes/cm. The present inventive membrane preferably has a titer reduction of at least about 108 against T1 bacteriophage, more preferably also against PR772 coliphage, and even more preferably also against PP7 bacteriophage. The present inventive membrane can have a thickness of about 20 mils or less and even as low as about 5 mils or less. The present invention also provides a method of preparing such a membrane by providing a casting solution comprising polyvinylidene fluoride and a solvent therefor, heating the casting solution to a uniform temperature of about 57 .degree.C to about 60 .degree.C, spreading the casting solution onto a substrate to form a film, quenching the film in a quench bath so as to form a porous membrane, and washing and drying the porous membrane.
|
