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Prof. Li-Cheng Jheng
National Kaohsiung University of Science and Technology

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0 Fuel Cells
0 Membrane
0 Composite
0 polymer and materials chemistry
0 nano and functional materials

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Journal article
Published: 26 August 2021 in Polymers
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A quaternized polybenzimidazole (PBI) membrane was synthesized by grafting a dimethylimidazolium end-capped side chain onto PBI. The organic–inorganic hybrid membrane of the quaternized PBI was prepared via a silane-induced crosslinking process with triethoxysilylpropyl dimethylimidazolium chloride. The chemical structure and membrane morphology were characterized using NMR, FTIR, TGA, SEM, EDX, AFM, SAXS, and XPS techniques. Compared with the pristine membrane of dimethylimidazolium-functionalized PBI, its hybrid membrane exhibited a lower swelling ratio, higher mechanical strength, and better oxidative stability. However, the morphology of hydrophilic/hydrophobic phase separation, which facilitates the ion transport along hydrophilic channels, only successfully developed in the pristine membrane. As a result, the hydroxide conductivity of the pristine membrane (5.02 × 10−2 S cm−1 at 80 °C) was measured higher than that of the hybrid membrane (2.22 × 10−2 S cm−1 at 80 °C). The hydroxide conductivity and tensile results suggested that both membranes had good alkaline stability in 2M KOH solution at 80 °C. Furthermore, the maximum power densities of the pristine and hybrid membranes of dimethylimidazolium-functionalized PBI reached 241 mW cm−2 and 152 mW cm−2 at 60 °C, respectively. The fuel cell performance result demonstrates that these two membranes are promising as AEMs for fuel cell applications.

ACS Style

Li-Cheng Jheng; Cheng-Wei Cheng; Ko-Shan Ho; Steve Lien-Chung Hsu; Chung-Yen Hsu; Bi-Yun Lin; Tsung-Han Ho. Dimethylimidazolium-Functionalized Polybenzimidazole and Its Organic–Inorganic Hybrid Membranes for Anion Exchange Membrane Fuel Cells. Polymers 2021, 13, 2864 .

AMA Style

Li-Cheng Jheng, Cheng-Wei Cheng, Ko-Shan Ho, Steve Lien-Chung Hsu, Chung-Yen Hsu, Bi-Yun Lin, Tsung-Han Ho. Dimethylimidazolium-Functionalized Polybenzimidazole and Its Organic–Inorganic Hybrid Membranes for Anion Exchange Membrane Fuel Cells. Polymers. 2021; 13 (17):2864.

Chicago/Turabian Style

Li-Cheng Jheng; Cheng-Wei Cheng; Ko-Shan Ho; Steve Lien-Chung Hsu; Chung-Yen Hsu; Bi-Yun Lin; Tsung-Han Ho. 2021. "Dimethylimidazolium-Functionalized Polybenzimidazole and Its Organic–Inorganic Hybrid Membranes for Anion Exchange Membrane Fuel Cells." Polymers 13, no. 17: 2864.

Journal article
Published: 21 December 2020 in Polymers
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Triethylenetetramine (TETA) and thiourea complexed Cobalt(II) (Co(II)) ions are used as cathode catalysts for proton exchanged membrane fuel cells (PEMFCs) under the protection of polyaniline (PANI) which can become a conducting medium after calcination. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) spectra clearly reveal the presence of typical carbon nitride and sulfide bonds of the calcined Nitrogen (N)- or Sulfur (S)-doped co-catalysts. Clear (002) and (100) planes of carbon-related X-ray diffraction patterns are found for co-catalysts after calcination, related to the formation of a conducting medium after the calcination of PANI. An increasing intensity ratio of the D to G band of the Raman spectra reveal the doping of N and S elements. More porous surfaces of co-catalysts are found in scanning electronic microscopy (SEM) micropictures when prepared in the presence of both TETA and thiourea (CoNxSyC). Linear sweep voltammetry (LSV) curves show the highest reducing current to be 4 mAcm−2 at 1600 rpm for CoNxSyC, indicating the necessity for both N- and S-doping. The membrane electrode assemblies (MEA) prepared with the cathode made of CoNxSyC produces the highest maximum power density, close to 180 mW cm−2.

ACS Style

Wen-Yao Huang; Li-Cheng Jheng; Tar-Hwa Hsieh; Ko-Shan Ho; Yen-Zen Wang; Yi-Jhun Gao; Po-Hao Tseng. Calcined Co(II)-Triethylenetetramine, Co(II)- Polyaniline-Thiourea as the Cathode Catalyst of Proton Exchanged Membrane Fuel Cell. Polymers 2020, 12, 3070 .

AMA Style

Wen-Yao Huang, Li-Cheng Jheng, Tar-Hwa Hsieh, Ko-Shan Ho, Yen-Zen Wang, Yi-Jhun Gao, Po-Hao Tseng. Calcined Co(II)-Triethylenetetramine, Co(II)- Polyaniline-Thiourea as the Cathode Catalyst of Proton Exchanged Membrane Fuel Cell. Polymers. 2020; 12 (12):3070.

Chicago/Turabian Style

Wen-Yao Huang; Li-Cheng Jheng; Tar-Hwa Hsieh; Ko-Shan Ho; Yen-Zen Wang; Yi-Jhun Gao; Po-Hao Tseng. 2020. "Calcined Co(II)-Triethylenetetramine, Co(II)- Polyaniline-Thiourea as the Cathode Catalyst of Proton Exchanged Membrane Fuel Cell." Polymers 12, no. 12: 3070.

Article
Published: 15 October 2020 in Journal of Polymer Science
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Poly(ethylene oxide)‐b‐poly(butadiene‐co‐acrylonitrile)‐b‐poly(ethylene oxide) (PEO‐b‐PBN‐b–PEO) triblock copolymers with three different compositions were synthesized from poly(ethylene glycol) methyl ethers and carboxylic acid‐terminated poly(butadiene‐co‐acrylonitrile) (CTBN) by ester coupling reaction at room temperature. The PEO‐b‐PBN‐b‐PEO was incorporated into anhydride cured epoxy thermosets to improve the fracture toughness by the formation of either nano‐sized spherical micelles or micron‐sized vesicles. The polymer chemical structure was confirmed by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and gel permeation chromatography. The morphology of PEO‐b‐PBN‐b–PEO within the epoxy thermosets was investigated using a transmission electron microscope, an atomic force microscope, and a scanning electron microscope. Also, we conducted impact testing and plane‐strain fracture toughness testing to evaluate the fracture toughness in terms of the impact strength and the critical stress intensity factors (KIC) for the modified epoxy thermosets. The results revealed that all the PEO‐b‐PBN‐b‐PEO triblock copolymers are more effective in the toughening of epoxy thermoset compare to CTBN. We found that the 5 wt% PEO‐b‐PBN‐b‐PEO modified epoxy thermoset containing micron‐sized vesicles exhibited the highest KIC, which was 3.23 times as high as the KIC of pristine epoxy thermoset. Besides, the glass transition temperature remained and the tensile modulus did not reduce remarkably when the amount of PEO‐b‐PBN‐b‐PEO added into epoxy was 5 wt%.

ACS Style

Li‐Cheng Jheng; I‐Hsin Wang; Tsung‐Han Hsieh; Chin‐Ting Fan; Chi‐Hui Hsiao; Chien‐Pang Wu; Ming‐Tsong Leu; Ting‐Yu Chang. Toughening of epoxy thermosets with nano‐sized or micron‐sized domains of poly(ethylene oxide)‐ b ‐poly (butadiene‐ co ‐acrylonitrile)‐ b ‐poly (ethylene oxide) triblock copolymers synthesized using room temperature ester coupling reaction. Journal of Polymer Science 2020, 138, 1 .

AMA Style

Li‐Cheng Jheng, I‐Hsin Wang, Tsung‐Han Hsieh, Chin‐Ting Fan, Chi‐Hui Hsiao, Chien‐Pang Wu, Ming‐Tsong Leu, Ting‐Yu Chang. Toughening of epoxy thermosets with nano‐sized or micron‐sized domains of poly(ethylene oxide)‐ b ‐poly (butadiene‐ co ‐acrylonitrile)‐ b ‐poly (ethylene oxide) triblock copolymers synthesized using room temperature ester coupling reaction. Journal of Polymer Science. 2020; 138 (13):1.

Chicago/Turabian Style

Li‐Cheng Jheng; I‐Hsin Wang; Tsung‐Han Hsieh; Chin‐Ting Fan; Chi‐Hui Hsiao; Chien‐Pang Wu; Ming‐Tsong Leu; Ting‐Yu Chang. 2020. "Toughening of epoxy thermosets with nano‐sized or micron‐sized domains of poly(ethylene oxide)‐ b ‐poly (butadiene‐ co ‐acrylonitrile)‐ b ‐poly (ethylene oxide) triblock copolymers synthesized using room temperature ester coupling reaction." Journal of Polymer Science 138, no. 13: 1.

Journal article
Published: 14 September 2020 in Molecules
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To facilitate broad applications and enhance bioactivity, resveratrol was esterified to resveratrol butyrate esters (RBE). Esterification with butyric acid was conducted by the Steglich esterification method at room temperature with N-ethyl-N′-(3-dimethylaminopropyl) carbodiimide (EDC) and 4-dimethyl aminopyridine (DMAP). Our experiments demonstrated the synthesis of RBE through EDC- and DMAP-facilitated esterification was successful and that the FTIR spectra of RBE revealed absorption (1751 cm−1) in the ester region. 13C-NMR spectrum of RBE showed a peak at 171 ppm corresponding to the ester group and peaks between 1700 and 1600 cm−1 in the FTIR spectra. RBE treatment (25 or 50 μM) decreased oleic acid-induced lipid accumulation in HepG2 cells. This effect was stronger than that of resveratrol and mediated through the downregulation of p-ACC and SREBP-2 expression. This is the first study demonstrating RBE could be synthesized by the Steglich method and that resulting RBE could inhibit lipid accumulation in HepG2 cells. These results suggest that RBE could potentially serve as functional food ingredients and supplements for health promotion.

ACS Style

You-Lin Tain; Li-Cheng Jheng; Sam K. C. Chang; Yu-Wei Chen; Li-Tung Huang; Jin-Xian Liao; Chih-Yao Hou. Synthesis and Characterization of Novel Resveratrol Butyrate Esters That Have the Ability to Prevent Fat Accumulation in a Liver Cell Culture Model. Molecules 2020, 25, 4199 .

AMA Style

You-Lin Tain, Li-Cheng Jheng, Sam K. C. Chang, Yu-Wei Chen, Li-Tung Huang, Jin-Xian Liao, Chih-Yao Hou. Synthesis and Characterization of Novel Resveratrol Butyrate Esters That Have the Ability to Prevent Fat Accumulation in a Liver Cell Culture Model. Molecules. 2020; 25 (18):4199.

Chicago/Turabian Style

You-Lin Tain; Li-Cheng Jheng; Sam K. C. Chang; Yu-Wei Chen; Li-Tung Huang; Jin-Xian Liao; Chih-Yao Hou. 2020. "Synthesis and Characterization of Novel Resveratrol Butyrate Esters That Have the Ability to Prevent Fat Accumulation in a Liver Cell Culture Model." Molecules 25, no. 18: 4199.

Journal article
Published: 25 August 2020 in Polymers
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In order to enhance the thermomechanical behaviors of epoxy molding compounds, the hexagonal boron nitride (h-BN) fillers were incorporated in a ketone mesogenic liquid crystalline epoxy (K–LCE) matrix to prepare a high-performance epoxy composites. The h-BN was modified by surface coupling agent 3-aminopropyltriethoxysilane (APTES). The grafting of silane molecules onto the surface of BN fillers improved the compatibility and homogeneous dispersion state of BN fillers in the K–LCE matrix with a strong interface interaction. The surface-modified BN fillers were characterized using Fourier transform infrared spectroscopy. The thermomechanical properties and morphologies of K–LCE/BN composites loading with different contents of modified BN fillers, ranging from 0.50 to 5.00 wt%, were investigated. These results show that modified BN fillers uniformly dispersed in K–LCE matrix, contributing to the enhancement in storage modulus, glass transition temperatures, impact strength and reduction in the coefficient of thermal expansion (CTE). The thermal stability and char yield of the K–LCE/BN composites were increased by increasing the amount of modified BN fillers and the thermal decomposition temperatures of composites were over 370 °C. The thermal conductivity of the K–LCE/BN composites was up to 0.6 W/m·K, for LC epoxy filled with 5.00-wt%-modified BN fillers. Furthermore, the K–LCE/BN composites have excellent thermal and mechanical properties compared to those of the DGEBA/BN composites.

ACS Style

Yi-Sheng Lin; Steve Lien-Chung Hsu; Tsung-Han Ho; Li-Cheng Jheng; Yu-Hsiang Hsiao. Preparation and Thermomechanical Properties of Ketone Mesogenic Liquid Crystalline Epoxy Resin Composites with Functionalized Boron Nitride. Polymers 2020, 12, 1913 .

AMA Style

Yi-Sheng Lin, Steve Lien-Chung Hsu, Tsung-Han Ho, Li-Cheng Jheng, Yu-Hsiang Hsiao. Preparation and Thermomechanical Properties of Ketone Mesogenic Liquid Crystalline Epoxy Resin Composites with Functionalized Boron Nitride. Polymers. 2020; 12 (9):1913.

Chicago/Turabian Style

Yi-Sheng Lin; Steve Lien-Chung Hsu; Tsung-Han Ho; Li-Cheng Jheng; Yu-Hsiang Hsiao. 2020. "Preparation and Thermomechanical Properties of Ketone Mesogenic Liquid Crystalline Epoxy Resin Composites with Functionalized Boron Nitride." Polymers 12, no. 9: 1913.

Journal article
Published: 26 March 2020 in Materials
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The small sized copper nanoparticles (Cu-NPs), prepared in the presence of triethylene tetramine (TETA) and assisted with microwave irradiation, have an extremely low melting temperature. Melting of the small sizezd Cu-NPs can be triggered by the heat generated from the e-beam irradiation during SEM and TEM image construction. The dispersed Cu atoms around the agglomerated big Cu particles can undergo recrystallization immediately due to the strong driving force of the huge temperature difference to normal melting temperature (Tm = 1085 °C). Some of the Cu-NPs with bigger sizes also recrystallize and agglomerate into dense, big particles. According to X-ray diffraction patterns, these particles can agglomerate into compact, ordered Cu crystals in less than five minutes at 60 °C. The melting and recrystallization related endothermic and exothermic phase transitions of Cu-NPs can be found from differential scanning calorimeter (DSC) thermograms and optical microscopic pictures.

ACS Style

Li-Cheng Jheng; Yen-Zen Wang; Wen-Yao Huang; Ko-Shan Ho; Cheng-Hsien Tsai; Ching-Tang Huang; Huang-Shian Tsai. Melting and Recrystallization of Copper Nanoparticles Prepared by Microwave-Assisted Reduction in the Presence of Triethylenetetramine. Materials 2020, 13, 1507 .

AMA Style

Li-Cheng Jheng, Yen-Zen Wang, Wen-Yao Huang, Ko-Shan Ho, Cheng-Hsien Tsai, Ching-Tang Huang, Huang-Shian Tsai. Melting and Recrystallization of Copper Nanoparticles Prepared by Microwave-Assisted Reduction in the Presence of Triethylenetetramine. Materials. 2020; 13 (7):1507.

Chicago/Turabian Style

Li-Cheng Jheng; Yen-Zen Wang; Wen-Yao Huang; Ko-Shan Ho; Cheng-Hsien Tsai; Ching-Tang Huang; Huang-Shian Tsai. 2020. "Melting and Recrystallization of Copper Nanoparticles Prepared by Microwave-Assisted Reduction in the Presence of Triethylenetetramine." Materials 13, no. 7: 1507.

Journal article
Published: 19 August 2019 in Polymers
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Calcinated tris(ethylenediamine)iron(III) chloride was used as a non-precious metal catalyst (NPMCs) for a proton exchanged membrane fuel cell (PEMFC) under the protection of polyaniline (PANI), which behaves as both nitrogen source and carbon supporter. The optimal ratio of FeCl3/EDA was found to be close to 1/3 under the consideration of the electrocatalytic performance, such as better oxygen reduction reaction (ORR) and higher power density. Two-stage calcination, one at 900 °C in N2 and the other at 800 °C in mixed gases of N2 and NH3, result in an FeNxC catalyst (FeNC-900-800-A) with pretty high specific surface area of 1098 m2·g-1 covered with both micro- and mesopores. The ORR active sites focused mainly on Fe-Nx bonding made of various pyridinic, pyrrolic, and graphitic N-s after calcination. The max. power density reaches 140 mW·cm-2 for FeNC-900-800-A, which is superior to other FeNxC catalysts, experiencing only one-stage calcination in N2. The FeNxC demonstrates only 10 mV half-wave-voltage (HWV) loss at 1600 rpm after 1000 redox cycles, as compared to be 27 mV for commercial Pt/C catalyst in the durability test.

ACS Style

Yen-Zen Wang; Wen-Yao Huang; Tar-Hwa Hsieh; Li-Cheng Jheng; Ko-Shan Ho; Sin-Wei Huang; Liang Chao. FeNxC Based Catalysts Prepared by the Calcination of [email protected] as the Cathode-Catalyst of Proton Exchange Membrane Fuel Cell. Polymers 2019, 11, 1368 .

AMA Style

Yen-Zen Wang, Wen-Yao Huang, Tar-Hwa Hsieh, Li-Cheng Jheng, Ko-Shan Ho, Sin-Wei Huang, Liang Chao. FeNxC Based Catalysts Prepared by the Calcination of [email protected] as the Cathode-Catalyst of Proton Exchange Membrane Fuel Cell. Polymers. 2019; 11 (8):1368.

Chicago/Turabian Style

Yen-Zen Wang; Wen-Yao Huang; Tar-Hwa Hsieh; Li-Cheng Jheng; Ko-Shan Ho; Sin-Wei Huang; Liang Chao. 2019. "FeNxC Based Catalysts Prepared by the Calcination of [email protected] as the Cathode-Catalyst of Proton Exchange Membrane Fuel Cell." Polymers 11, no. 8: 1368.

Accepted manuscript
Published: 05 February 2019 in Nanotechnology
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A variety of conductive films made of a hybrid of two conductive nanomaterials have been used as stretchable electrodes or interconnectors, desirable for stretchable electronic devices. Their intrinsic stretchability of electrical conductivity would allow for accommodating mechanical strain to a certain extent under various deformations. However, few efforts have been made to enhance the interactions between two conductive components in a hybrid system. Herein, we reported new conductive films with tri-layer sandwich structures based on CNTs and AgNWs, encapsulated in silicone rubber, exhibited high stretchability along with insignificant piezoresistivity. They would be suitable to be stretchable interconnectors. A successive vacuum filtration method was used to stack the conductive components layer by layer. The effects of the stacking sequence and the interactions between layers on the stretchability and stability of electrical properties under mechanical deformations were studied. In the case of a tri-layer conductive film comprising two CNT outer layers and one AgNW central layer in presence of enhanced interfacial interactions, it showed exceptionally durability of withstanding repetitive deformations.

ACS Style

Li-Cheng Jheng; Chi-Hui Hsiao; Wen-Ching Ko; Steve Lien-Chung Hsu; Yu-Lun Huang. Conductive films based on sandwich structures of carbon nanotubes/silver nanowires for stretchable interconnects. Nanotechnology 2019, 30, 235201 .

AMA Style

Li-Cheng Jheng, Chi-Hui Hsiao, Wen-Ching Ko, Steve Lien-Chung Hsu, Yu-Lun Huang. Conductive films based on sandwich structures of carbon nanotubes/silver nanowires for stretchable interconnects. Nanotechnology. 2019; 30 (23):235201.

Chicago/Turabian Style

Li-Cheng Jheng; Chi-Hui Hsiao; Wen-Ching Ko; Steve Lien-Chung Hsu; Yu-Lun Huang. 2019. "Conductive films based on sandwich structures of carbon nanotubes/silver nanowires for stretchable interconnects." Nanotechnology 30, no. 23: 235201.

Journal article
Published: 01 February 2017 in International Journal of Hydrogen Energy
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ACS Style

Li-Cheng Jheng; Chin-Kuen Tai; Steve Lien-Chung Hsu; Bi-Yun Lin; Likey Chen; Bo-Cheng Wang; Lieh-Kuang Chiang; Wen-Ching Ko. Study on the alkaline stability of imidazolium and benzimidazolium based polyelectrolytes for anion exchange membrane fuel cells. International Journal of Hydrogen Energy 2017, 42, 5315 -5326.

AMA Style

Li-Cheng Jheng, Chin-Kuen Tai, Steve Lien-Chung Hsu, Bi-Yun Lin, Likey Chen, Bo-Cheng Wang, Lieh-Kuang Chiang, Wen-Ching Ko. Study on the alkaline stability of imidazolium and benzimidazolium based polyelectrolytes for anion exchange membrane fuel cells. International Journal of Hydrogen Energy. 2017; 42 (8):5315-5326.

Chicago/Turabian Style

Li-Cheng Jheng; Chin-Kuen Tai; Steve Lien-Chung Hsu; Bi-Yun Lin; Likey Chen; Bo-Cheng Wang; Lieh-Kuang Chiang; Wen-Ching Ko. 2017. "Study on the alkaline stability of imidazolium and benzimidazolium based polyelectrolytes for anion exchange membrane fuel cells." International Journal of Hydrogen Energy 42, no. 8: 5315-5326.

Journal article
Published: 01 August 2016 in Journal of Power Sources
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ACS Style

Li-Cheng Jheng; Wesley Jen-Yang Chang; Steve Lien-Chung Hsu; Po-Yang Cheng. Durability of symmetrically and asymmetrically porous polybenzimidazole membranes for high temperature proton exchange membrane fuel cells. Journal of Power Sources 2016, 323, 57 -66.

AMA Style

Li-Cheng Jheng, Wesley Jen-Yang Chang, Steve Lien-Chung Hsu, Po-Yang Cheng. Durability of symmetrically and asymmetrically porous polybenzimidazole membranes for high temperature proton exchange membrane fuel cells. Journal of Power Sources. 2016; 323 ():57-66.

Chicago/Turabian Style

Li-Cheng Jheng; Wesley Jen-Yang Chang; Steve Lien-Chung Hsu; Po-Yang Cheng. 2016. "Durability of symmetrically and asymmetrically porous polybenzimidazole membranes for high temperature proton exchange membrane fuel cells." Journal of Power Sources 323, no. : 57-66.

Journal article
Published: 01 June 2014 in Journal of Membrane Science
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ACS Style

Li-Cheng Jheng; Steve Lien-Chung Hsu; Bi-Yun Lin; Yi-Lun Hsu. Quaternized polybenzimidazoles with imidazolium cation moieties for anion exchange membrane fuel cells. Journal of Membrane Science 2014, 460, 160 -170.

AMA Style

Li-Cheng Jheng, Steve Lien-Chung Hsu, Bi-Yun Lin, Yi-Lun Hsu. Quaternized polybenzimidazoles with imidazolium cation moieties for anion exchange membrane fuel cells. Journal of Membrane Science. 2014; 460 ():160-170.

Chicago/Turabian Style

Li-Cheng Jheng; Steve Lien-Chung Hsu; Bi-Yun Lin; Yi-Lun Hsu. 2014. "Quaternized polybenzimidazoles with imidazolium cation moieties for anion exchange membrane fuel cells." Journal of Membrane Science 460, no. : 160-170.

Journal article
Published: 01 January 2014 in Journal of Materials Chemistry A
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A novel asymmetric polybenzimidazole (PBI) membrane used for high temperature proton exchange membrane fuel cells has been successfully fabricated by a soft-template method using the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]) as the porogen. Typically, the asymmetric PBI membrane exhibits a double-layer structure comprising a dense layer and a porous layer with a distinguishable boundary. The morphology and asymmetry of the porous structure have been characterized by SEM micrographs. The density difference between the polymer matrix and the porogen can be considered as the driving force for developing the asymmetrical structure. Phosphoric acid-doped asymmetric PBI with a high porosity exhibited considerably enhanced doping levels and proton conductivity. For example, a doping level of up to 23.6 and a proton conductivity as high as 6.26 × 10−2 S cm−1 were achieved. Moreover, the crosslinking modification of asymmetric PBIs had beneficial effects on the mechanical strength and oxidative stability, which were investigated. We have also demonstrated the fuel cell performance of a membrane electrode assembly (MEA) based on the asymmetric PBI at elevated temperatures under anhydrous conditions in the present work.

ACS Style

Li-Cheng Jheng; Steve Lien-Chung Hsu; Tzung-Yu Tsai; Wesley Jen-Yang Chang. A novel asymmetric polybenzimidazole membrane for high temperature proton exchange membrane fuel cells. Journal of Materials Chemistry A 2014, 2, 4225 .

AMA Style

Li-Cheng Jheng, Steve Lien-Chung Hsu, Tzung-Yu Tsai, Wesley Jen-Yang Chang. A novel asymmetric polybenzimidazole membrane for high temperature proton exchange membrane fuel cells. Journal of Materials Chemistry A. 2014; 2 (12):4225.

Chicago/Turabian Style

Li-Cheng Jheng; Steve Lien-Chung Hsu; Tzung-Yu Tsai; Wesley Jen-Yang Chang. 2014. "A novel asymmetric polybenzimidazole membrane for high temperature proton exchange membrane fuel cells." Journal of Materials Chemistry A 2, no. 12: 4225.

Journal article
Published: 08 July 2013 in Journal of Applied Polymer Science
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ACS Style

Steve Lien-Chung Hsu; Yung-Chung Lin; Tsung-Yu Tasi; Li-Cheng Jheng; Cheng-Hsun Shen. Synthesis and properties of fluorine- and siloxane-containing polybenzimidazoles for high temperature proton exchange membrane fuel cells. Journal of Applied Polymer Science 2013, 130, 4107 -4112.

AMA Style

Steve Lien-Chung Hsu, Yung-Chung Lin, Tsung-Yu Tasi, Li-Cheng Jheng, Cheng-Hsun Shen. Synthesis and properties of fluorine- and siloxane-containing polybenzimidazoles for high temperature proton exchange membrane fuel cells. Journal of Applied Polymer Science. 2013; 130 (6):4107-4112.

Chicago/Turabian Style

Steve Lien-Chung Hsu; Yung-Chung Lin; Tsung-Yu Tasi; Li-Cheng Jheng; Cheng-Hsun Shen. 2013. "Synthesis and properties of fluorine- and siloxane-containing polybenzimidazoles for high temperature proton exchange membrane fuel cells." Journal of Applied Polymer Science 130, no. 6: 4107-4112.

Journal article
Published: 26 November 2012 in International Journal of Hydrogen Energy
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Composite membranes used for proton exchange membrane fuel cells comprising of polybenzimidazole (PBI) and carbon nanotubes with certain functional groups were studied, because they could enhance both the mechanical property and fuel cell performance at the same time. In this study, sodium poly(4-styrene sulfonate) functionalized multiwalled carbon nanotubes (MWNT-poly(NaSS))/PBI and imidazole functionalized multiwalled carbon nanotubes (MWNT-imidazole)/PBI composite membranes were prepared. The functionalization of carbon nanotubes involving non-covalent modification and covalent modification were confirmed by FITR, XPS, Raman spectroscopy, and TGA. Compared to unmodified MWNTs and MWNT-poly(NaSS), MWNT-imidazole provided more significant mechanical reinforcement due to its better compatibility with PBI. For MWNT-poly(NaSS)/PBI and MWNT-imidazole/PBI composite membranes at their saturated doping levels, the proton conductivities were up to 5.1 × 10−2 and 4.3 × 10−2 S/cm at 160 °C under anhydrous condition respectively, which were slightly higher than pristine PBI (2.8 × 10−2 S/cm). Also, MWNT-poly(NaSS)/PBI and MWNT-imidazole/PBI composite membranes showed relatively improved fuel cell performance at 170 °C compared to pristine PBI.

ACS Style

Li-Cheng Jheng; Ching-Ying Huang; Steve Lien-Chung Hsu. Sulfonated MWNT and imidazole functionalized MWNT/polybenzimidazole composite membranes for high-temperature proton exchange membrane fuel cells. International Journal of Hydrogen Energy 2012, 38, 1524 -1534.

AMA Style

Li-Cheng Jheng, Ching-Ying Huang, Steve Lien-Chung Hsu. Sulfonated MWNT and imidazole functionalized MWNT/polybenzimidazole composite membranes for high-temperature proton exchange membrane fuel cells. International Journal of Hydrogen Energy. 2012; 38 (3):1524-1534.

Chicago/Turabian Style

Li-Cheng Jheng; Ching-Ying Huang; Steve Lien-Chung Hsu. 2012. "Sulfonated MWNT and imidazole functionalized MWNT/polybenzimidazole composite membranes for high-temperature proton exchange membrane fuel cells." International Journal of Hydrogen Energy 38, no. 3: 1524-1534.

Journal article
Published: 07 June 2012 in Polymer
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For studied blends of amorphous glycol-modified poly(ethylene terephthalate) (PETG) and semicrystalline polyethylene naphthalate (PEN), melt miscibility is understood from the linear variation of a single glass transition temperature (Tg) over the entire composition range. The diluent effect of PETG component severely retarded the crystallization of PEN component within blends. Nevertheless, after being through isothermal stretching at 120 °C, crystallization was able to progress efficiently during heating in a continuous manner. Instead of being thermally relaxed back to amorphous state, parallel sliding motions of stretched PEN segments toward crystallization appear rather dominant. Within stretched blends, the PETG content emerged as a critical factor to the crystallinity increase of PEN fraction and the absence of lattice defect, instead of behaving as a diluent component. Furthermore, as being indicated by in-situ small-angle X-ray experiments, regular lamellar stacking gradually developed within stretched blends through heating, which indicates the involvement of thermally activated self-association of randomly distributed crystalline lamellae. With including a higher fraction of PETG component, these secondary ordering processes including lamellar thickening can be activated at lower temperature. Hence, the accompanied thermal relaxation of flexible PETG segment is inferred able to lubricate the sliding of stretched PEN segments in amorphous regions via lowering encountered frictional hindrance, and thus enhance both primary and secondary ordering processes within stretched blends.

ACS Style

Li-Cheng Jheng; Chun-Yen Yang; Ming-Tsong Leu; Keng-Hao Hsu; Jyh-Horng Wu; Jrjeng Ruan; Kuo-Chen Shih. Novel impacts of glycol-modified poly(ethylene terephthalate)(PETG) to crystallization behavior of polyethylene naphthalate (PEN) within stretched miscible blends. Polymer 2012, 53, 2758 -2768.

AMA Style

Li-Cheng Jheng, Chun-Yen Yang, Ming-Tsong Leu, Keng-Hao Hsu, Jyh-Horng Wu, Jrjeng Ruan, Kuo-Chen Shih. Novel impacts of glycol-modified poly(ethylene terephthalate)(PETG) to crystallization behavior of polyethylene naphthalate (PEN) within stretched miscible blends. Polymer. 2012; 53 (13):2758-2768.

Chicago/Turabian Style

Li-Cheng Jheng; Chun-Yen Yang; Ming-Tsong Leu; Keng-Hao Hsu; Jyh-Horng Wu; Jrjeng Ruan; Kuo-Chen Shih. 2012. "Novel impacts of glycol-modified poly(ethylene terephthalate)(PETG) to crystallization behavior of polyethylene naphthalate (PEN) within stretched miscible blends." Polymer 53, no. 13: 2758-2768.

Journal article
Published: 01 March 2012 in European Polymer Journal
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ACS Style

Yuhsin Tsai; Li-Cheng Jheng; Steve Lien-Chung Hsu. Thermogelling polymers composed of poly(cyclohexylenedimethylene adipate) and poly(ethylene glycol). European Polymer Journal 2012, 48, 541 -548.

AMA Style

Yuhsin Tsai, Li-Cheng Jheng, Steve Lien-Chung Hsu. Thermogelling polymers composed of poly(cyclohexylenedimethylene adipate) and poly(ethylene glycol). European Polymer Journal. 2012; 48 (3):541-548.

Chicago/Turabian Style

Yuhsin Tsai; Li-Cheng Jheng; Steve Lien-Chung Hsu. 2012. "Thermogelling polymers composed of poly(cyclohexylenedimethylene adipate) and poly(ethylene glycol)." European Polymer Journal 48, no. 3: 541-548.

Journals
Published: 01 September 2011 in Journal of Materials Chemistry
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Cross-linked porous polybenzimidazole (PBI) membranes were prepared by mixing a low-molecular-weight compound (porogen) and a cross-linker with the polymer to form cross-linked polymer membranes in order to increase the mechanical strength and proton conductivity. SEM images of the cross-section of the porous polymer membranes show the pore size and morphology. The cross-linking by p-xylylene dichloride can effectively improve the mechanical properties of the porous PBI membranes after phosphoric acid doping. The CpPBI-60 membrane, which is doped with 9 moles of phosphoric acid, has a tensile modulus of 0.45 GPa. The good mechanical strength of the cross-linked porous PBI membranes makes them able to hold more phosphoric acid and, consequently, have higher proton conductivity. Fenton's test indicated that the covalently cross-linked structure played an important role in the radical oxidative stability of the porous membranes. The doping level of phosphoric acid in the cross-linked porous PBI membranes showed that the enhanced conductivity was due to the increase of porosity, which results in the increase of acid uptake. Impedance analysis showed that the conductivity of the cross-linked porous PBI membranes could reach 2.1 × 10−2 S cm−1 at 160 °C under anhydrous conditions.

ACS Style

Cheng-Hsun Shen; Li-Cheng Jheng; Steve Lien-Chung Hsu; Jacob Tse-Wei Wang. Phosphoric acid-doped cross-linked porous polybenzimidazole membranes for proton exchange membrane fuel cells. Journal of Materials Chemistry 2011, 21, 15660 -15665.

AMA Style

Cheng-Hsun Shen, Li-Cheng Jheng, Steve Lien-Chung Hsu, Jacob Tse-Wei Wang. Phosphoric acid-doped cross-linked porous polybenzimidazole membranes for proton exchange membrane fuel cells. Journal of Materials Chemistry. 2011; 21 (39):15660-15665.

Chicago/Turabian Style

Cheng-Hsun Shen; Li-Cheng Jheng; Steve Lien-Chung Hsu; Jacob Tse-Wei Wang. 2011. "Phosphoric acid-doped cross-linked porous polybenzimidazole membranes for proton exchange membrane fuel cells." Journal of Materials Chemistry 21, no. 39: 15660-15665.

Journal article
Published: 31 January 2010 in Polymer Degradation and Stability
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ACS Style

Yuhsin Tsai; Li-Cheng Jheng; Chi-Yuan Hung. Synthesis, properties and enzymatic hydrolysis of biodegradable alicyclic/aliphatic copolyesters based on 1,3/1,4-cyclohexanedimethanol. Polymer Degradation and Stability 2010, 95, 72 -78.

AMA Style

Yuhsin Tsai, Li-Cheng Jheng, Chi-Yuan Hung. Synthesis, properties and enzymatic hydrolysis of biodegradable alicyclic/aliphatic copolyesters based on 1,3/1,4-cyclohexanedimethanol. Polymer Degradation and Stability. 2010; 95 (1):72-78.

Chicago/Turabian Style

Yuhsin Tsai; Li-Cheng Jheng; Chi-Yuan Hung. 2010. "Synthesis, properties and enzymatic hydrolysis of biodegradable alicyclic/aliphatic copolyesters based on 1,3/1,4-cyclohexanedimethanol." Polymer Degradation and Stability 95, no. 1: 72-78.