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Epoxy membranes that have interconnected pores with different surface structures were synthesized using the chemically induced phase separation process. The epoxy membrane was produced from a mixture of epoxy resin, D.E.R. 331, and the curing agent, 2,4,6-tris-(dimethylaminomethyl) phenol (DMP-30) in diisobutyl ketone, while covered with a contacting film. It was found that the surface morphology of the epoxy membranes could be changed by the fraction of DIBK, or by using different contacting films of which the surface pore sizes ranged from 0.15 through 2.4 lm. Furthermore, ethanol permeabilities through the epoxy membranes were measured. The permeabilities are approximately 3-4700 L/m 2 h bar and depend on either the bulk morphology or the skin structure of the membranes. The epoxy membranes with various porosities and ethanol permeabilities could be also prepared using different compositions of the DMP-30 and diethylene triamine (DETA)) mixture. A modified Hagen-Poiseuille equation was proposed to describe the effects of the surface and bulk porosity on ethanol permeability. It was found that at low permeabilities, most of the resistance of the surface layers is higher than that of the bulk section.

A novel and simple method for producing crosslinked polymers with controlled surface morphology is demonstrated in this study. The porous crosslinked polymers were made via stepwise polymerization of a mixture of epoxy resin, D.E.R. 331, and diethylene triamine in diisobutyl ketone (DIBK). Both the surface and bulk morphology of the cured polymers are dependent on the solvent fraction of the reactive solution. When the concentration of DIBK was more than about 30 vol %, chemically induced phase separation (CIPS) occurred during cure at 30 °C, and closed spherical pores, about 4 μm in diameter, appeared in the bulk of the crosslinked polymers, whose diameter increased to about 4.5 and 9 μm when the solvent was increased to 40% and 50%, respectively. The surface morphology of the epoxy networks is different from that of the bulk. Smaller pore size or dense skin was formed via the CIPS process, which can be tailored by covering the reactive solution with different contacting films during cure. The competition between the solvent‐rich and polymer‐rich phase absorbed onto the surface of contacting film could change the surface morphology. Therefore, the porous crosslinked polymers having similar bulk morphology could be prepared with a variety of surface structures. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011

In an effort to exploit low-cost tin and sulfur as active materials in lithium-ion hybrid capacitors, we prepare a SnS−Sn/carbon nanotube (CNT) negative electrode through molten slag coating of acidified carbon nanotubes (CNTs) with a minimum level of surface oxidation. The capacity of this sulfur-containing electrode behaves more reversibly and less decaying in an ether-based electrolyte of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and LiNO 3 than the generalpurpose electrolyte of LiPF 6 . On the positive electrode, a nitrogen-doped carbon, KPN900, is prepared in-house with a high Brunauer−Emmett−Teller (BET) surface area of 3280 m 2 g −1 to increase the capacitance of microporous carbon. Intriguingly, the rate performance of the KPN900 electrode is slowed down by the LiTFSI electrolyte, compared with the LiPF 6 electrolyte, since a part of its capacitive component is switched to the diffusive component, while its total double-layer capacitance remains the same. Soaked in the LiTFSI electrolyte, a hybrid capacitor of KPN900//SnS− Sn/CNT, with a capacity of 97.5 mAh g −1 , is capable of storing an energy of 143 Wh kg −1 with a retrieving power of 148 W kg −1 , when the charging voltage is 3.8 V. The stability test of this cell, in a 4:1 mass ratio, shows a capacity retention of 78.8% after 2400 cycles of charging and discharging at 1.0 A g −1 .

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