Porous membrane structure and method
US6854603B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 1, 2003 |
| Grant date | Feb 15, 2005 |
| Priority date | — |
| Expiry date | Jul 1, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249991
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of treating a membrane comprises the steps of providing a membrane with surfaces that define a plurality of pores extending through the membrane. Providing a dispersion of oleophobic fluoropolymer solids. Stabilizing the dispersion with a stabilizing agent. Diluting the dispersion with a wetting agent. Wetting surfaces which define the pores in the membrane with the diluted and stabilized dispersion. Removing the wetting agent and the stabilizing agent from the membrane. Coalescing the oleophobic fluoropolymer solids of the dispersion on surfaces that define pores in the membrane. A composite membrane comprises a porous membrane having a plurality of interconnecting pores extending through the membrane and made from a material which tends to absorb oils and certain contaminating surfactants. A coating is disposed on surfaces of the nodes and fibrils defining the interconnecting passages in the membrane. The coating comprises oleophobic fluoropolymer solids coalesced on surfaces of the nodes and fibrils to provide oil and surfactant resistance to the composite membrane without completely blocking pores in the membrane. The composite membrane is gas permeable, liquid penetra…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.