Effect of solvents on the characteristics of Nafion®/PTFE composite membranes for fuel cell applications

Ramya, K.; Velayutham, G.; Subramaniam, C. K.; Rajalakshmi, N.; Dhathathreyan, K. S.

doi:10.1016/j.jpowsour.2005.12.082

Cited by 51 publications

(32 citation statements)

References 23 publications

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“…A similar trend was observed for P MeOH and performance in a DMFC; moreover, performance deterioration with increasing MeOH concentration was less significant for the composite membrane than for the N112 membrane (Lin et al 2005). Ramya et al (2006) showed that adding ethylene glycol, a high-boiling-point solvent, could probably further improve impregnation and tighten the composite membrane, while adding n-hexane, a low-boiling-point solvent, results in fissure formation. Teng et al (2013) repeated the methods of Liu et al (2003) and presented a membrane prepared from a 5 wt.% Nafion/DMF solution, which looked essentially the same as a Nafion 212 membrane both to the naked eye and in scanning electron microscopy (SEM) pictures.…”

Section: Isotropic Pore-filling Membranessupporting

confidence: 69%

Understanding methods of preparation and characterization of pore-filling polymer composites for proton exchange membranes: a beginner’s guide

Gloukhovski

Freger

Tsur

2017

Reviews in Chemical Engineering

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Abstract Composite membranes based on porous support membranes filled with a proton-conducting polymer appear to be a promising approach to develop novel proton exchange membranes (PEMs). It allows optimization of the properties of the filler and the matrix separately, e.g. for maximal conductivity of the former and maximal physical strength of the latter. In addition, the confinement itself can alter the properties of the filling ionomer, e.g. toward higher conductivity and selectivity due to alignment and restricted swelling. This article reviews the literature on PEMs prepared by filling of submicron and nanometric size pores with Nafion and other proton-conductive polymers. PEMs based on alternating perfluorinated and non-perfluorinated polymer systems and incorporation of fillers are briefly discussed too, as they share some structure/transport relationships with the pore-filling PEMs. We also review here the background knowledge on structural and transport properties of Nafion and proton-conducting polymers in general, as well as experimental methods concerned with preparation and characterization of pore-filling membranes. Such information will be useful for preparing next-generation composite membranes, which will allow maximal utilization of beneficial characteristics of polymeric proton conductors and understanding the complicated structure/transport relationships in the pore-filling composite PEMs.

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Section: Isotropic Pore-filling Membranessupporting

confidence: 69%

Understanding methods of preparation and characterization of pore-filling polymer composites for proton exchange membranes: a beginner’s guide

Gloukhovski

Freger

Tsur

2017

Reviews in Chemical Engineering

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“…Therefore, a reasonable number of repeat units for PES and PTFE polymers should be determined. The solubility parameter (δ) defined as equation (1) [35,36], can be employed to (Table 2), consistent with values obtained from experiments (12.7 and 20.8 (J/cm 3 ) 0.5 for PES and PTFE, respectively) [41,42]. Therefore, both PES and PTFE polymer chains with ten repeat units were chosen for the following MD simulations, and optimized structures of them are shown in Figure 7.…”

Section: Simulationsmentioning

confidence: 56%

Miscibility analysis of polyethersulfone and polytetrafluoroethylene using the molecular dynamics method

2015

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Investigation of the miscibility between polyethersulfone (PES) and polytetrafluoroethylene (PTFE) will be helpful in the preparation of functional polymers. The miscibility between PES and PTFE in different proportions was studied using molecular dynamics (MD) simulations, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). PES and PTFE are partly miscible as the weight fraction of PES is less than 30 wt%. The interaction between PES and PTFE polymers cannot be chemical bonding, and the non-bond interaction between them will play an important role in the blending. The hydrogen bond interaction can be ignored due to its low contribution to the non-bonded energies. Compared with hydrogen bond and electrostatic interactions, Van der Waals (vdW) shows a large influence on the non-bond interaction of pure PTFE; but its contribution in PES/PTFE blends decreases with the increasing addition of PES. The presence of PTFE suppresses the mobility of PES chains; nevertheless, the mobility of PTFE chains is unremarkably influenced by PES.

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“…The properties of the substrate used and the membrane are given in Table 1. The SEM images of the substrate and the composite membrane have been discussed in detail earlier [14]. Conductivity measurements were made by sandwiching the membrane between conducting plates and measuring the impedance.…”

Section: Resultsmentioning

confidence: 99%

“…Nafion composite membranes with porous Teflon, polypropylene, nylon, and Celgard substrates have been studied and their properties are reported in the literature [9,10]. The composite membranes based on expanded PTFE has been the subject of study of many researchers and studies on methods to reduce the resistance of the membranes through surface modification of EPTFE [11][12][13], changes in the solvent solubility parameter [14], addition of additives during membrane fabrication [15] have been investigated.…”

Section: Introductionmentioning

confidence: 99%

Performance of a 1 kW Class Nafion-PTFE Composite Membrane Fuel Cell Stack

Krishnamurthy¹,

Ramya²,

Samban³

2012

International Journal of Chemical Engineering

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Composite membranes have been prepared by impregnation of Nafion into the expanded polytetrafluoroethylene (EPTFE) matrix. Nafion loading in the composite membranes was kept constant at 2 mg/cm 2 . The lower amount of electrolyte per unit area in the composite membranes offers cost advantages compared to conventional membrane of 50 µm thickness with an electrolyte loading of ∼9 mg/cm 2 . Composite membranes (30 µm thickness) were found to have higher thermal stability and mechanical strength compared to the conventional membranes (50 µm thickness). The performance of the membrane electrode assembly made with these composite membranes was comparable to that of the conventional membranes. Single cells fabricated from these MEAs were tested for their performance and durability before scaling them up for large area. The performance of a 20-cell stack of active area 330 cm 2 fabricated using these membranes is reported.

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Effect of solvents on the characteristics of Nafion®/PTFE composite membranes for fuel cell applications

Cited by 51 publications

References 23 publications

Understanding methods of preparation and characterization of pore-filling polymer composites for proton exchange membranes: a beginner’s guide

Understanding methods of preparation and characterization of pore-filling polymer composites for proton exchange membranes: a beginner’s guide

Miscibility analysis of polyethersulfone and polytetrafluoroethylene using the molecular dynamics method

Performance of a 1 kW Class Nafion-PTFE Composite Membrane Fuel Cell Stack

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