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In this work, S40 (sulfonated poly(styrene-block-(ethylene-ran-butylene)-block-styrene) with 40% degree of sulfonation)-ZrP (zirconium phosphate) composite membranes, serving as proton conducting membranes for direct methanol fuel cells, were prepared via a precursor infiltration method. The obtained S40-ZrP membranes exhibited homogeneous distribution of ZrP nanoplatlets within continuous proton conducting sulfonated polystyrene domains of the microphase separated S40 matrix. Employing different solvent of the infiltrating ZrP precursor solution could tailor the loading, the geometry and the crystallinity of ZrP, which considerably affect the transport properties. S40-N3, the composite membrane containing only 3 wt% of ZrP using weak basic N-methyl-2-pyrrolidone as the solvent, exhibited a remarkable 16 fold increment in selectivity as compared to the parent S40 membrane due to enhanced proton conductivity and significantly suppressed methanol permeability. S40-N3 also exhibited improved mechanical properties to enable the integrity of the corresponding membrane electrode assembly during DMFC operation, leading to a power density of 66 mW cm−2 (1 M methanol at 60 °C) and a maximum current density of 450 mA cm−2 without cathode flooding. The DMFC performance was better than a DMFC single cell using Nafion 117 by 50% under the same setup. Enhancement in proton conductivity at low relative humidity was also observed for S40-N3 due to the strong water retention capability of ZrP, suggesting a good potential for both DMFC and PEMFC.

Traditional diazonaphthoquinone (DNQ) positive photoresists are widely used for TFT-LCD array process. Current LTPS technology has more than 600ppi resolution is required for small or middle-sized TFT liquid crystal display panels. One of the ways to enhance resolution is to apply i-line single exposure system instead of traditional g/h/ibroadband exposure system. We have been developing i-line chemically amplified photoresist ECA 200 series for the next generation flat panel display (FPD). ECA 200 consists of three components: a phenol resin, a photo acid generator and dissolution enhancer. We applied two different types of dissolution enhancers with two different kinds of protected groups to our resist materials. As a result, we achieved higher sensitivity, higher resolution, less footing of the resist profile and reduced standing wave effect compared with traditional DNQ photoresists. In addition, we have found further property of photoresist that does not need post exposure bake (PEB) process. This resist has a great advantage at most of current panel plants without PEB process.

In this article, we report the syntheses and charac- terizations of a series of novel block polyelectrolytes, poly(sty- rene-block-sulfonated hydroxystyrene) (PS-b-sPHS), containing pendant sulfonic acid groups attached to the backbone via propyl spacers in the sPHS domain. PS-b-sPHS with various compositions were synthesized via anionic polymerization and the following analogous chemistry to achieve accurate control of molecular weight (Mw), narrow polydispersity and high degree of sulfonation. Proton exchange membranes (PEMs) were prepared from PS-b-sPHS with sulfonic acids in either po- tassium salts or tetra-alkylammonium salts via solvent casting and following treatments. Some unique morphologies, such as hallow channels and lamellar arrangement of strings of beads, were observed as a consequence of equilibrium between microphase separation and columbic interactions between pol- yelectrolytes. The transportation properties were found to closely relate to the morphologies of the PEMs. The combina- tion of microphase separation of block polyelectrolytes and freedom of movement of pendent alkylsulfonic acids was dem- onstrated to effectively enhance the proton transport and sup- press the methanol crossover for the PEMs, leading to the selectivity higher than Nafion 117 by five times at most. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 2325-2338, 2011