@article{oai:repo.qst.go.jp:00078513,
 author = {Duy Tap, Tran and Ly Nguyen, La and Zhao, Yue and Hasegawa, Shin and Sawada, Shinichi and Quang Hung, Nguyen and Anh Tuyen, Luu and Maekawa, Yasunari and Zhao, Yue and Shin, Hasegawa and Shinichi, Sawada and Yasunari, Maekawa},
 issue = {3},
 journal = {Macromolecular Chemistry and Physics},
 month = {Dec},
 note = {The changes of the lamellar periods (L1D), thickness of lamellar crystals (Lc), and amorphous layers (La) within the stacked lamellae of poly(styrenesulfonic acid)‐grafted poly(ethylene‐co‐tetrafluoroethylene) polymer electrolyte membranes (ETFE‐PEMs), induced by the preparation and water‐absorbing steps are investigated using the small‐angle X‐ray scattering method. The L1D values of all the samples quickly increase at a grafting degree (GD) range of less than 19% and then level off. The solvent‐induced recrystallization is observed at the early stage of grafting (GD < 10%) and at successive sulfonation and hydration steps. The L1D, La, and Lc of dry and hydrated PEMs show similar values at higher GD ranges (>34%), leading to the conclusion that most water molecules in the PEMs with higher GDs exist at the outside of the lamellar stacks. Accordingly, for the PEMs with low GD (<19%), all the hydrophilic graft‐polymers (ion‐channels) locate in the lamellar stacks and are strongly restricted by lamellar crystalline layers, which suppress the swelling of the PEMs. The unique lamellar structures of ETFE‐PEMs characterized by La and Lc are well connected with the high conductance and mechanical properties of the membranes, and are suitable for fuel cell applications.},
 title = {SAXS Investigation on Morphological Change in Lamellar Structures During Propagation Steps of Graft‐Type Polymer Electrolyte Membranes for Fuel Cell Applications},
 volume = {221},
 year = {2019}
}