Process for the preparation of hydrophilic membranes and such membranes
USRE34296E · kind E · reissue
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1990 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Dec 17, 2010 |
Classification
- Technology area (CPC —)General
Abstract
This invention relates to a process for the preparation of hydrophilic membranes by coagulation of a solution of at least one hydrophobic polymer and at least one hydrophilic polymer in a suitable solvent medium in a coagulation medium. The process according to the invention is characterized in that hydrophilic microfiltration and/or ultrafiltration membranes are prepared by cross-linking the hydrophilic polymer which is present in or on the obtained membrane matrix after the coagulation in an essentially non-swollen state and fixing same as such in or on the polymer matrix. Advantageously the solvents and the undesirable components of the coagulation medium are removed whereby the hydrophilic polymer is converted into an essentially non-swollen state prior to cross-linking. The removal of the undesirable components from the membrane takes place by means of a non-solvent for the hydrophilic polymer according to the invention. Finally, the invention relates to hydrophilic microfiltration- and/or ultrafiltration membranes, flat or tubular of a hollow fiber structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.