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In the midst of this era of nanotechnology and shrinking device size, block copolymers have evolved from their use in traditional application areas (e.g., adhesives, additives, and elastomers) to enable the development of materials for new emerging and more advanced technologies. This review discusses the use of block copolymers to generate nanoporous polymers that can be used either directly, in applications such as membrane filtration, or subsequently as a template for the formation of other nanostructured materials. The work within describes published research from the beginning of 2005 to the present discussing nanoporous materials in the context of: (i) nanolithography and new alignment technologies, (ii) monoliths, (iii) new fabrication techniques, and (iv) membranes. A summary and perspective on the current direction of the stimulating area of block copolymer derived nanoporous materials concludes the review.

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Water vapor permeability of cold‐ and warm‐water fish skin gelatins films was evaluated and compared with different types of mammalian gelatins. Alaskan pollock and salmon gelatins were extracted from frozen skins, others were obtained from commercial sources. Water vapor permeability of gelatin films was determined considering differences on percent relative humidity (%RH) at the film underside. Molecular weight distribution, amino acid composition, gel strength, viscoelastic properties, pH, and clarity were also determined for each gelatin. Water vapor permeability of cold‐water fish gelatin films (0.93 gmm/m2hkPa) was significantly lower than warm‐water fish and mammalian gelatin films (1.31 and 1.88 gmm/m2hkPa, respectively) at 25 °C, 0/80 %RH through 0.05‐mm thickness films. This was related to increased hydrophobicity due to reduced amounts of proline and hydroxyproline in cold‐water fish gelatins. As expected, gel strength and gel setting temperatures were lower for cold‐water fish gelatin than either warm‐water fish gelatins or mammalian gelatins. This study demonstrated significant differences in physical, chemical, and rheological properties between mammalian and fish gelatins. Lower water vapor permeability of fish gelatin films can be useful particularly for applications related to reducing water loss from encapsulated drugs and refrigerated or frozen food systems.

A versatile method for preparing amorphous degradable elastomers with tunable properties that can be easily fabricated into a wide variety of shape-specific devices was investigated. Completely amorphous, liquid poly(ester ether) prepolymers with number-average molecular weights between 4 and 6 x 10(3) g/mol were prepared via condensation polymerization. These liquid prepolymers were then thermally cross-linked to form degradable elastomeric structures. The ability to vary the composition of these liquid prepolymers allows for easy control of the mechanical and degradation properties of the resulting elastomeric structures. Materials can be designed to completely degrade in vitro over a range of 30 days to 6 months, while the Young's modulus can be varied over 3 orders of magnitude (G = 0.02-20 MPa). Also, the liquid nature of these prepolymers makes them amenable to a wide variety of fabrication techniques. Using traditional and modified imprint lithography techniques, we have fabricated devices that demonstrate a wide variety of biologically applicable topologies, which could easily be extended to fabricate devices with more complex geometries. Until now, no method has combined this ease and speed of fabrication with the ability to control the mechanical and degradation properties of the resulting elastomers over such a broad range.