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With a three-cylinder spark-ignition (SI) engine, formaldehyde (HCHO) and methanol (CH3OH) emission characteristics as well as the three-way catalytic converter (TWC) conversion efficiency were investigated when it ran on gasoline, M10, M20, and M85 (gasoline blended with 10, 20, and 85% of methanol in volume), respectively. HCHO and CH3OH were detected by gas chromatography (GC) with a pulsed discharge helium ionization detector (PDHID). Experimental results show that HCHO emission increases with engine speed, while CH3OH emission from a methanol/gasoline blend-fueled engine decreases with it. HCHO emission from a gasoline-fueled engine varies in a “U” curve with the engine torque. The addition of 10% methanol in gasoline doubles the HCHO emission. The increasing methanol fraction greatly improves HCHO and CH3OH emission; their concentrations are both approximately linear to the amount of cyclically supplied fuel methanol. CH3OH can be totally removed by lightened-off TWC. However, the HCHO concentration may increase rather than decrease via the conversion of TWC at high engine speeds.

A novel series of polyaromatic ionomers with similar equivalent weights but very different sulphonic acid distributions along the ionomer backbone has been designed and prepared. By synthetically organising the sequence‐distribution so that it consists of fully defined ionic segments (containing singlets, doublets or quadruplets of sulphonic acid groups) alternating strictly with equally well‐defined nonionic spacer segments, a new class of polymers which may be described as microblock ionomers has been developed. These materials exhibit very different properties and morphologies from analogous randomly substituted systems. Progressively extending the nonionic spacer length in the repeat unit (maintaining a constant equivalent weight by increasing the degree of sulphonation of the ionic segment) leads to an increasing degree of nanophase separation between hydrophilic and hydrophobic domains in these materials. Membranes cast from ionomers with the more highly phase‐separated morphologies show significantly higher onset temperatures for uncontrolled swelling in water. This new type of ionomer design has enabled the fabrication of swelling‐resistant hydrocarbon membranes, suitable for fuel cell operation, with very much higher ion exchange capacities (>2 meq g–1) than those previously reported in the literature. When tested in a fuel cell at high temperature (120 °C) and low relative humidity (35% RH), the best microblock membrane matched the performance of Nafion 112. Moreover, comparative low load cycle testing of membrane ‐electrode assemblies suggests that the durability of the new membranes under conditions of high temperature and low relative humidity is superior to that of conventional perfluorinated materials.

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