Anomalous surface relaxation process in polystyrene ultrathin films

Kei Ichi Akabori, Keiji Tanaka, Tisato Kajiyama, Atsushi Takahara

研究成果: ジャーナルへの寄稿記事

48 引用 (Scopus)

抄録

Monodisperse polystyrene (PS) films with various thicknesses were spun-coated on silicon wafers with native oxide layer. Surface relaxation behavior in the PS films was studied as a function of thickness by lateral force microscopy (LFM). In the case of a thick PS film, a clear lateral force peak corresponding to surface αa-relaxation process of segmental motion was observed at a temperature much lower than the bulk glass transition temperature, Tg. As the film became thinner than 3-4 times the radius of gyration of an unperturbed consistent chain, the peak on lateral force vs temperature curve started to broaden out with decreasing thickness and eventually split into two peaks. The appearance temperature of the surface αa-relaxation peak was invariant with respect to the film thickness even in such an ultrathin state, meaning that surface Tg was insensitive to the thickness. On the other hand, the ultrathinning-induced relaxation process, called surface β-relaxation, was strongly dependent on the thickness in terms of relaxation temperature and apparent activation energy. Finally, possible origins of the surface β-relaxation process were proposed.

元の言語英語
ページ(範囲)4937-4943
ページ数7
ジャーナルMacromolecules
36
発行部数13
DOI
出版物ステータス出版済み - 7 1 2003

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Surface relaxation
Ultrathin films
Polystyrenes
Relaxation processes
Temperature
Silicon wafers
Oxides
Film thickness
Microscopic examination
Activation energy
Thin films

All Science Journal Classification (ASJC) codes

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

これを引用

Anomalous surface relaxation process in polystyrene ultrathin films. / Akabori, Kei Ichi; Tanaka, Keiji; Kajiyama, Tisato; Takahara, Atsushi.

:: Macromolecules, 巻 36, 番号 13, 01.07.2003, p. 4937-4943.

研究成果: ジャーナルへの寄稿記事

Akabori, Kei Ichi ; Tanaka, Keiji ; Kajiyama, Tisato ; Takahara, Atsushi. / Anomalous surface relaxation process in polystyrene ultrathin films. :: Macromolecules. 2003 ; 巻 36, 番号 13. pp. 4937-4943.
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