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Enomoto, Kazuyuki; Yuasa, Kanako*; Kato, Jun*; Matsushita, Harumi*; Yamashita, Takashi*; Ito, Kazuo*; Yoshida, Masaru; Maekawa, Yasunari
no journal, ,
A color forming performance for fabricating nanoscale patterned polymer films has been examined using electron beam direct writing (EBDW) techniques. Upon EB irradiation the poly(methyl methacrylate) film consisting of 3 wt% bis(dimethylamino)benzhydrol and the equimolar sulfonium salt has an absorption band at 560 nm, which is assigned to protonated benzhydrol. The appearance of the new band at 560 nm with an isosbestic point in the spectral changes of indicates the quantitative transformation from colorless benzhydrol to the protonated form. The film is then exposed with a raster scanning by EBDW. Upon EB irradiation they also undergo chemical changes to provide optical differentiation between the exposed and unexposed regions. The blue-colored line/space patterns of 100 - 200 nm with a dose of 10 
C/cm
are achieved.
Hasegawa, Shin; Maekawa, Yasunari
no journal, ,
To develop application in a fuel cell, a chemical stability is one of the most important parameter. For chemical resistance, fluorinated polymers having repeating unit -CF
-CF- like poly (tetrafluoroethylene) have excellent performance. A radiation grafting technique allows us to introduce ion conducing regions directly into polymer films. However, there have been no reports for successful preparation of grafted chains using fluorinated monomers. In this paper, we report the first successful preparation of the PEM having fluorinated grafted chains by radiation-induced graft polymerization.
Maekawa, Yasunari; Takahashi, Shuichi; Hanh, T. T.*; Okonogi, Hiroyuki*; Hagiwara, Tokio*
no journal, ,
Polymer electrolyte membranes (PEMs) consisting of alkylsulfonic acid in grafting chains can be prepared by radiation-induced graft polymerization of methyl acrylate (MA) onto a poly(ethylene-co-tetrafluoroethylene) (ETFE) film, followed by the sulfonation of MA units in the grafting chains using an equimolar complex of chlorosulfonic acid and dioxane. The sulfonation reaction accompanied equimolar decarboxylation of the MA unit (substitution of carboxylic acid with sulfonic acid) to give the PEMs with conductivity of 0.01-0.11 S/cm. Furthermore, the replacement of the MA unit with methyl metacrylate (MMA) as a comonomer in grafting chains enhances the stability of the PEM at higher temperatures.