Membranes have been typically used for filtration, reverse osmosis (hyperfiltration), dialysis, pervaporation, and gas separation applications. A solid membrane can be made of synthetic polymers, natural macromolecules, inorganic compounds, ceramic or metallic materials, and are generally fabricated through sintering, stretching, extrusion, phase inversion and etching, or casting. Porous membranes are advantageous in their low resistance to mass transfer of solutes due to the increased permeation rate from the pores. Therefore, porous membranes have been employed for various applications including separation of mixtures of proteins and macromolecules, salt concentration, and sterilization. They can also serve as 3-D matrices for chemical and biochemical mass exchange or reactions to take place, or for cells or other living organisms to grow, and have wider applications.
This invention describes the compositions and methods for fabricating polymers into porous materials with very high specific surface areas. This novel phase-separation technique generates porous polymeric materials (porosity is typically > 80 or 90%) with very high specific surface areas and a unique nano fibrous structure. These porous polymeric materials may be formed in a variety of porous with high surface areas. Their structures and properties depend on the polymer/solvent systems and phase-separation conditions. This invention is specifically for polymeric (or substantially polymeric) materials with very high surface areas with high porosity. The polymers can be synthetic or natural, homo- or co-polymers, single polymer type or polymer blends. Chemically or biologically active or inert materials can be involved as additives or major component. The polymers can be physically, chemically, or/and biologically modified to improve certain properties or function. Such modification can be carried out before fabrication (raw materials) or after fabrication of the porous materials.
Applications and Advantages
- Scaffolding materials for tissue regeneration
- Medical devices (e.g., artificial kidneys)
- Controlled release devices
- Wound dressings
- Matrix materials for chemical reactors
- Separation membranes, filters, catalysis-nl-systems
- Wide range of building blocks: homopolymers,-nl-copolymers, random or block or graft
- Possibility to incorporate non-polymeric-nl-materials, additives
- Ability to physically, chemically, or-nl-biologically modify functions and properties-nl-(pre- or post-fabrication)