Abstract
The segmental mobility of a typical amorphous polymer, polystyrene, at the interfaces with solid substrates was noninvasively examined by fluorescence lifetime measurements using evanescent wave excitation in conjunction with coarse-grained molecular dynamics simulation. The glass transition temperature (Tg) was discernibly higher at the interface than in the internal bulk region. Measurements at different incident angles of excitation pulses revealed that Tg became higher closer to the interface. The gradient became more marked with an increasing difference in the free energy at the interface between the polymer and solid substrate. The Tg value at the interface decreased with decreasing molecular weight. However, the decrement for the interfacial Tg was not as much as that for the bulk Tg, due to the restriction of chain end portions by the substrate. Finally, it was observed that when a film became thinner than 50 nm, the depressed mobility at the interface coupled with the enhanced mobility induced by the presence of the surface. The experimental and simulation results were in good accord with each other.
| Original language | English |
|---|---|
| Pages (from-to) | 4571-4577 |
| Number of pages | 7 |
| Journal | Journal of Physical Chemistry B |
| Volume | 113 |
| Issue number | 14 |
| DOIs | |
| Publication status | Published - Apr 9 2009 |
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All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry
Cite this
Interfacial mobility of polymers on inorganic solids. / Tanaka, Keiji; Tateishi, Yohei; Okada, Yohei; Nagamura, Toshihiko; Doi, Masao; Morita, Hiroshi.
In: Journal of Physical Chemistry B, Vol. 113, No. 14, 09.04.2009, p. 4571-4577.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Interfacial mobility of polymers on inorganic solids
AU - Tanaka, Keiji
AU - Tateishi, Yohei
AU - Okada, Yohei
AU - Nagamura, Toshihiko
AU - Doi, Masao
AU - Morita, Hiroshi
PY - 2009/4/9
Y1 - 2009/4/9
N2 - The segmental mobility of a typical amorphous polymer, polystyrene, at the interfaces with solid substrates was noninvasively examined by fluorescence lifetime measurements using evanescent wave excitation in conjunction with coarse-grained molecular dynamics simulation. The glass transition temperature (Tg) was discernibly higher at the interface than in the internal bulk region. Measurements at different incident angles of excitation pulses revealed that Tg became higher closer to the interface. The gradient became more marked with an increasing difference in the free energy at the interface between the polymer and solid substrate. The Tg value at the interface decreased with decreasing molecular weight. However, the decrement for the interfacial Tg was not as much as that for the bulk Tg, due to the restriction of chain end portions by the substrate. Finally, it was observed that when a film became thinner than 50 nm, the depressed mobility at the interface coupled with the enhanced mobility induced by the presence of the surface. The experimental and simulation results were in good accord with each other.
AB - The segmental mobility of a typical amorphous polymer, polystyrene, at the interfaces with solid substrates was noninvasively examined by fluorescence lifetime measurements using evanescent wave excitation in conjunction with coarse-grained molecular dynamics simulation. The glass transition temperature (Tg) was discernibly higher at the interface than in the internal bulk region. Measurements at different incident angles of excitation pulses revealed that Tg became higher closer to the interface. The gradient became more marked with an increasing difference in the free energy at the interface between the polymer and solid substrate. The Tg value at the interface decreased with decreasing molecular weight. However, the decrement for the interfacial Tg was not as much as that for the bulk Tg, due to the restriction of chain end portions by the substrate. Finally, it was observed that when a film became thinner than 50 nm, the depressed mobility at the interface coupled with the enhanced mobility induced by the presence of the surface. The experimental and simulation results were in good accord with each other.
UR - http://www.scopus.com/inward/record.url?scp=65249159621&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=65249159621&partnerID=8YFLogxK
U2 - 10.1021/jp810370f
DO - 10.1021/jp810370f
M3 - Article
C2 - 19275200
AN - SCOPUS:65249159621
VL - 113
SP - 4571
EP - 4577
JO - Journal of Physical Chemistry B Materials
JF - Journal of Physical Chemistry B Materials
SN - 1520-6106
IS - 14
ER -