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Liquid phase ultraviolet irradiation was used to graft the mixtures of N-isopropylacrylamide and glycidyl methacrylate to a linear low-density polyethylene film (thickness of 30 μm) surface. Xanthone was used as photoinitiator, which was coated on the film surface earlier. The surface of the grafted polyethylene samples were characterized by attenuated total-reflection IR spectroscopy and scanning electron microscopy. Elemental analysis indicated that the NIPAAm fraction with respect to GMA in the graft copolymer increased with increasing NIPAAm ratio in the comonomer feed solution. The reactivity ratios of NIPAAm and GMA monomers determined in the present graft copolymerization system were found to be 0,31 ± 0,1 and 4,8 ± 0,2, respectively. It was found that the epoxy groups of GMA-grafted chains in the NIPAAm/GMA-grafted films have the ability to react with ethylenediamine (En). The aminated NIPAAm/GMA-grafted film had an excellent ability to adsorb cupric ion. The temperature-responsive character of the resulting grafted films was evaluated by measuring the water absorbency of the grafted NIPAAm/ GMA when immersed in water and/or methanol at 5 to 50 0 C.

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In this study, electrolyte membranes based on polystyrene acrylonitrile (SAN) for Direct Methanol Fuel Cell application were prepared. The preparation was carried out in two steps. The first step was introduction of additives, silica and zeolite, as reinforcing agent on SAN, to obtain silica-reinforced SAN membrane, specified as SAN-Si, and zeolite-reinforced SAN membranae, specified as SAN-Z. The two reinforced membranes were then subjected to sulphonation using sulphuric acid, and the sulphonated membranes are specified as S-SAN-Si and S-SAN-Z, respectively. The characteristics of the membrane were described in terms of the degree of sulphonation, ionic conductivity, methanol permeability, and percentage of swelling in water and methanol. The results obtained demonstrated that additives result in significant reduction of methanol crossover, as reflected by lower values of methanol permeability than that obtained for the membrane without additive. It was also found that zeolite functions relatively better than silica. For zeolite-modified membrane (S-SAN-Z) the ionic conductivity of 10.05 x 10 -6 S/cm was achieved. The membrane also marked by methanol permeability of 0.52 x 10 -6 , percentage of swelling of 5.12% in water and 2.58% in methanol. Thermal analysis using DSC technique revealed changes in glass transition from the original sample, in which the glass transition of the original sample, SAN, (55 0 C), sulphonated SAN, S-SAN, (83.36 0 C), silica-modified membrane S-SAN-Si (79.86 0 C), and zeolite-modified membrane S-SAN-Z (79.29 0 C). Addition of additive was also found to influence the surface characteristics of the membranes as revealed by SEM analysis, in which the surface changed from smooth for the original sample into rough for the reinforced samples with both additives.