タイトル（掲載誌）JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
一般注記Rodlike capsules consisting of a calcium carbonate core and a crosslinked polystyrene shell were synthesized, and the glass transition temperature (T_g) and characteristic length of the glass transition ξ(T_g) for the thin outer shells were investigated by temperature-modulated differential scanning calorimetry. The shell thickness ranged from 20 to 129 nm. The ratio of the Tg for the outer shell to the bulk T_g increases with decreasing shell thickness d. The d-dependence of T_g is interpreted in terms of a simple two-layer model which assumes that an immobile layer exists near the core-shell interface. Shells of hollow capsules unexpectedly exhibit a similar d-dependence of T_g to that for the filled capsules. This is characteristic of the crosslinked polymeric shells, and is attributed to certain spatial heterogeneity of crosslink distribution, and/or to the unstable configuration in the ultrathin shell that does not undergo relaxation due to the crosslink. The latter idea is based on the assumption that unstable configurational state is responsible for the Tg shift from the bulk value observed for nanosized polymeric materials. The ratio of the characteristic length for the shell of the filled capsule to that of the bulk ξ_f(T_g) /ξ_b(T_g) decreases with decreasing d. The results are interpreted in terms of the configurational entropy, and it is also suggested that the configurational state of network polymer chains in the shell affects the characteristic length.
一次資料へのリンクURLhttps://u-fukui.repo.nii.ac.jp/?action=repository_action_common_download&item_id=22629&item_no=1&attribute_id=22&file_no=1
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）