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A detailed investigation has been carried out of the pre-polymerisation modification of the polymer of intrinsic microporosity PIM-1 by the addition of two methyl (Me) groups to its spirobisindane unit to create a new chemically modified PIM-1 analogue, termed MePIM. Our work explores the effects of this modification on the porosity of PIM-1 and hence on its gas sorption properties. MePIM was successfully synthesised using either low (338 K) or high (423 K) temperature syntheses. It was observed that introduction of methyl groups to the spirobisindane part of PIM-1 generates additional microporous spaces, which significantly increases both surface area and hydrogen storage capacity. The BET surface area (N2 at 77 K) was increased by ~ 12.5%, resulting in a ~ 25% increase of hydrogen adsorption after modification. MePIM also maintains the advantages of good processability and thermal stability. This work provides new insights on a facile polymer modification that enables enhanced gas sorption properties. [ABSTRACT FROM AUTHOR]

Polymer of intrinsic microporosity PIM-1 was used for electrospun polymer nanofiber producing. After pyrolysis, the obtained nanofibers, in a form of entire mat, were used as a support for cathode electrocatalyst for high-temperature polymer electrolyte membrane fuel cell on polymer polybenzimidazole membrane. The material was characterized by the methods of standard contact porosimetry, Raman spectroscopy and scanning electron microscopy. The I-V curves for membrane-electrode assembly suggest a possibility of using the carbon material for electrodes in a fuel cell on polymer membrane. [ABSTRACT FROM AUTHOR]

The exploration and evaluation of new composites possessing both processability and enhanced hydrogen storage capacity are of significant interest for onboard hydrogen storage systems and fuel cell based electric vehicle development. Here we demonstrate the fabrication of composite membranes with sufficient mechanical properties for enhanced hydrogen storage that are based on a polymer of intrinsic microporosity (PIM-1) matrix containing nano-sized fillers: activated carbon (AX21) or metal–organic framework (MIL-101). This is one of the first comparative studies of different composite systems for hydrogen storage and, in addition, the first detailed evaluation of the diffusion kinetics of hydrogen in polymer-based nanoporous composites. The composite films were characterised by surface area and porosity analysis, hydrogen adsorption measurements, mechanical testing and gas adsorption modelling. The PIM-1/AX21 composite with 60 wt% AX21 provides enhanced hydrogen adsorption kinetics and a total hydrogen storage capacity of up to 9.35 wt% at 77 K; this is superior to the US Department of Energy hydrogen storage target. Tensile testing indicates that the ultimate stress and strain of PIM-1/AX21 are higher than those of the MIL-101 or PAF-1 containing composites, and are sufficient for use in hydrogen storage tanks. The data presented provides new insights into both the design and characterisation methods of polymer-based composite membranes. Our nanoporous polymer-based composites offer advantages over powders in terms of safety, handling and practical manufacturing, with potential for hydrogen storage applications either as means of increasing storage or decreasing operating pressures in high-pressure hydrogen storage tanks. [ABSTRACT FROM AUTHOR]

The development of alternative, non-fluorinated membranes for polymer electrolyte membrane fuel cells necessitates the co-development of a non-fluorinated electrode catalyst binder to ensure compatibility between membrane and electrode. However, most hydrocarbon based polymers have lower gas permeability than perfluorinated Nafion. In this work we tried to obtain a sulfonated, non-fluorinated binder based on PIM-1 (polymer of intrinsic microporosity 1) which has up to 2000 times higher permeability than Nafion. However, sulfonation was not straightforward and often led to degradative side reactions. Sulfonated polymers were too brittle to give stable membranes and the highest experimental IEC was 1.03 meq/g, significantly lower than the theoretical IEC of 3.2 meq/g (2 sulfonic acid groups per repeat unit). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]