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Endo, Yukihiro*; Fukaya, Yuki; Mochizuki, Izumi*; Takayama, Akari*; Hyodo, Toshio*; Hasegawa, Shuji*
Carbon, 157, p.857 - 862, 2020/02
Times Cited Count：23 Percentile：76.39(Chemistry, Physical)no abstracts in English
Park, J.*; Takayama, Toshio*; Asano, Masaharu; Maekawa, Yasunari; Kudo, Kazuaki*; Takayama, Toshio*
Polymer, 54(17), p.4570 - 4577, 2013/08
Times Cited Count：6 Percentile：19.37(Polymer Science)Graft-type sulfonated polybenzimidazole was prepared through radiation-induced graft polymerization of styrenes into an alicyclic polybenzimidazole film and subsequent sulfonation. The alicyclic polybenzimidazole, ChPBI, was prepared from 
-1,4-cyclohexanedicarboxylic acid and 3,3'-diaminobenzidine using typical polycondensation. Anisotropic domains with a size of several tens of micrometers were found in the ChPBI films casted from LiCl-containing 
,-dimethylacetamide. Irradiation of the ChPBI membranes with a 220 kGy dose of 
-rays created radical species with mean lifetimes of two days. The treatment of this membrane with a 50/50 (v/v) mixture of 1-propanol and styrene produced polystyrene graft chains. Sulfonation of the resulting grafted membrane with ClSOH
OH occurred selectively on the polystyrene grafts. The sulfonated films showed proton conductivity on the order of 10
to 10
S/cm with an ion exchange capacity between 2.1 and 2.9 mmol/g. SEM-EDX analysis of the membrane indicated the presence of macrophase separated domains up to 1 
m in diameter. The proton conductivity of the membrane did not decrease for 600 h at 120
C in liquid water.
Park, J.; Takayama, Toshio*; Kudo, Kazuaki*; Maekawa, Yasunari
no journal, ,
PEMs for fuel cells prepared by radiation-induced graft polymerization of styrene onto APBI and subsequent sulfonation showed low mechanical property. PBI, exhibited no grafting reactivity, was employed as a blend polymer to APBI to increase mechanical property of PEMs. Polymer blend (1/1) film showed grafting reactivity as high as APBI even though it contained only 50% of APBI. This might be due to the enhanced graft polymerization of styrene on APBI which was promoted by the increased amorphous regions in the polymer blend film. Sulfonated polymer blend film showed similar proton conductivity with PEMs of APBI, while they showed lower water uptakes and higher mechanical property.
Asano, Masaharu; Maekawa, Yasunari; Park, J.*; Takayama, Toshio*; Kudo, Kazuaki*
no journal, ,
no abstracts in English
Asano, Masaharu; Maekawa, Yasunari; Park, J.*; Takayama, Toshio*; Kudo, Kazuaki*
no journal, ,
no abstracts in English
Asano, Masaharu; Maekawa, Yasunari; Park, J.*; Takayama, Toshio*; Kudo, Kazuaki*
no journal, ,
no abstracts in English
Endo, Yukihiro*; Mochizuki, Izumi*; Fukaya, Yuki; Takayama, Akari*; Hyodo, Toshio*; Hasegawa, Shuji*
no journal, ,
no abstracts in English
