2. Experimental Section
2.1 Materials
Victrex PEEK (grade 450G), purchased by Victrex PLC (England) was used as the base polymer. Kynar flex 2801, PVDF-HFP (11-12% of hexafluoropropylene copolymer) was supplied by Arkema, Japan. Organically modified nanoclay, C 30B with a cation exchange capacity (CEC) of 90 meq/100 g was procured from M/s Southern clay Products. Conc.H2SO4 (98% pure) used as sulfonating agent was supplied by Merck lab grade. The catalysts, Pt black for the cathode and Pt/Ru black for the anode, were purchased from Johnson-Matthey, USA. Nafion® 5 wt-% binder solution from E.I. DuPont Company was used for membrane electrode assembly. Nafion® 117 membrane, from E.I. DuPont Company was chosen as the commercial sample to compare …show more content…
(2)
Swelling degree (%) = ("Lw - Ld" )" × 100" /"Ld" .......................................................................... (2) where Lw and Ld are the length of wet and dry membranes, respectively.
2.5.2 Oxidative stability by Fenton’s reagent test
Oxidative stability of the membranes was tested by immersing the membrane sample into 50 ml of Fenton’s reagent (30 % H2O2 containing 30 ppm FeSO4) at room temperature for 5 h. After desired time, the samples were taken out of the solution and weighed again. Oxidative stability was evaluated from the percentage of weight loss of the membrane sample.
2.5.3 Thermogravimetric Analysis (TGA)
Thermal stability of the membranes was determined using a thermogravimetric analyzer (Q 50, M/s TA Instruments). The membranes were heated from room temperature to 800°C at a heating rate of 20°C/min under nitrogen atmosphere.
2.5.4 Wide angle X-Ray Diffraction (WXRD)
The dispersion of C 30B particles in the hybrid membranes were successfully determined by WXRD studies. Test was performed by a X-Ray Diffractometer (M/s Shimadzu, Kyoto, Japan) using a Cu Kα ray of wavelength 1.541 °A over the range 2°≤ 2 ≤ 25° at …show more content…
Compartment A was filled with 50 ml of 2M methanol solution while compartment B was with the same amount of deionised water. Prior to the test, all the membranes were pre-hydrated for at least 24 h. The membrane with an active surface area of 4.91 cm2 was clamped tightly between two glass compartments. The concentration of methanol solution diffused from compartment A to B across the membrane was continuously examined with time using a digital density meter (DMA 5000, M/s Anton Paar) at a time interval of every 30 m. Before the experiment, the calibration curve for the density vs. the methanol concentration was prepared to measure actual methanol concentration in the compartment B. From the straight line plot of methanol concentration vs. permeation time, methanol concentration CB can be calculated by using the given
2.1 Materials
Victrex PEEK (grade 450G), purchased by Victrex PLC (England) was used as the base polymer. Kynar flex 2801, PVDF-HFP (11-12% of hexafluoropropylene copolymer) was supplied by Arkema, Japan. Organically modified nanoclay, C 30B with a cation exchange capacity (CEC) of 90 meq/100 g was procured from M/s Southern clay Products. Conc.H2SO4 (98% pure) used as sulfonating agent was supplied by Merck lab grade. The catalysts, Pt black for the cathode and Pt/Ru black for the anode, were purchased from Johnson-Matthey, USA. Nafion® 5 wt-% binder solution from E.I. DuPont Company was used for membrane electrode assembly. Nafion® 117 membrane, from E.I. DuPont Company was chosen as the commercial sample to compare …show more content…
(2)
Swelling degree (%) = ("Lw - Ld" )" × 100" /"Ld" .......................................................................... (2) where Lw and Ld are the length of wet and dry membranes, respectively.
2.5.2 Oxidative stability by Fenton’s reagent test
Oxidative stability of the membranes was tested by immersing the membrane sample into 50 ml of Fenton’s reagent (30 % H2O2 containing 30 ppm FeSO4) at room temperature for 5 h. After desired time, the samples were taken out of the solution and weighed again. Oxidative stability was evaluated from the percentage of weight loss of the membrane sample.
2.5.3 Thermogravimetric Analysis (TGA)
Thermal stability of the membranes was determined using a thermogravimetric analyzer (Q 50, M/s TA Instruments). The membranes were heated from room temperature to 800°C at a heating rate of 20°C/min under nitrogen atmosphere.
2.5.4 Wide angle X-Ray Diffraction (WXRD)
The dispersion of C 30B particles in the hybrid membranes were successfully determined by WXRD studies. Test was performed by a X-Ray Diffractometer (M/s Shimadzu, Kyoto, Japan) using a Cu Kα ray of wavelength 1.541 °A over the range 2°≤ 2 ≤ 25° at …show more content…
Compartment A was filled with 50 ml of 2M methanol solution while compartment B was with the same amount of deionised water. Prior to the test, all the membranes were pre-hydrated for at least 24 h. The membrane with an active surface area of 4.91 cm2 was clamped tightly between two glass compartments. The concentration of methanol solution diffused from compartment A to B across the membrane was continuously examined with time using a digital density meter (DMA 5000, M/s Anton Paar) at a time interval of every 30 m. Before the experiment, the calibration curve for the density vs. the methanol concentration was prepared to measure actual methanol concentration in the compartment B. From the straight line plot of methanol concentration vs. permeation time, methanol concentration CB can be calculated by using the given