Abstract
Water-soluble triblock copolymers have received much attention in industrial applications and scientific fields. We here show that femtosecond mid-IR pump-probe spectroscopy is useful to study the role of water in the temperature-induced self-assembly of triblock copolymers. Our experimental results suggest two distinct subpopulations of water molecules: those that interact with other water molecules and those involved in the hydration of a triblock copolymer surface. We find that the vibrational dynamics of bulk-like water is not affected by either micellation or gelation of triblock copolymers. The increased population of water interacting with ether oxygen atoms of the copolymer during the unimer to micelle phase transition is important evidence for the entropic role of water in temperature-induced micelle formation at a low copolymer concentration. In contrast, at the critical gelation temperature and beyond, the population of surface-associated water molecules interacting with ether oxygen atoms decreases, which indicates important enthalpic control by water. The present study on the roles of water in the two different phase transitions of triblock copolymers sheds new light on the underlying mechanisms of temperature-induced self-aggregation behaviors of amphiphiles that are ubiquitous in nature.
| Original language | English |
|---|---|
| Pages (from-to) | 3040-3047 |
| Number of pages | 8 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 8 |
| Issue number | 13 |
| DOIs | |
| Publication status | Published - 2017 Jul 6 |
Fingerprint
ASJC Scopus subject areas
- Materials Science(all)
Cite this
Role of Solvent Water in the Temperature-Induced Self-Assembly of a Triblock Copolymer. / Kundu, Achintya; Verma, Pramod Kumar; Cho, Minhaeng.
In: Journal of Physical Chemistry Letters, Vol. 8, No. 13, 06.07.2017, p. 3040-3047.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Role of Solvent Water in the Temperature-Induced Self-Assembly of a Triblock Copolymer
AU - Kundu, Achintya
AU - Verma, Pramod Kumar
AU - Cho, Minhaeng
PY - 2017/7/6
Y1 - 2017/7/6
N2 - Water-soluble triblock copolymers have received much attention in industrial applications and scientific fields. We here show that femtosecond mid-IR pump-probe spectroscopy is useful to study the role of water in the temperature-induced self-assembly of triblock copolymers. Our experimental results suggest two distinct subpopulations of water molecules: those that interact with other water molecules and those involved in the hydration of a triblock copolymer surface. We find that the vibrational dynamics of bulk-like water is not affected by either micellation or gelation of triblock copolymers. The increased population of water interacting with ether oxygen atoms of the copolymer during the unimer to micelle phase transition is important evidence for the entropic role of water in temperature-induced micelle formation at a low copolymer concentration. In contrast, at the critical gelation temperature and beyond, the population of surface-associated water molecules interacting with ether oxygen atoms decreases, which indicates important enthalpic control by water. The present study on the roles of water in the two different phase transitions of triblock copolymers sheds new light on the underlying mechanisms of temperature-induced self-aggregation behaviors of amphiphiles that are ubiquitous in nature.
AB - Water-soluble triblock copolymers have received much attention in industrial applications and scientific fields. We here show that femtosecond mid-IR pump-probe spectroscopy is useful to study the role of water in the temperature-induced self-assembly of triblock copolymers. Our experimental results suggest two distinct subpopulations of water molecules: those that interact with other water molecules and those involved in the hydration of a triblock copolymer surface. We find that the vibrational dynamics of bulk-like water is not affected by either micellation or gelation of triblock copolymers. The increased population of water interacting with ether oxygen atoms of the copolymer during the unimer to micelle phase transition is important evidence for the entropic role of water in temperature-induced micelle formation at a low copolymer concentration. In contrast, at the critical gelation temperature and beyond, the population of surface-associated water molecules interacting with ether oxygen atoms decreases, which indicates important enthalpic control by water. The present study on the roles of water in the two different phase transitions of triblock copolymers sheds new light on the underlying mechanisms of temperature-induced self-aggregation behaviors of amphiphiles that are ubiquitous in nature.
UR - http://www.scopus.com/inward/record.url?scp=85021862271&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85021862271&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.7b01008
DO - 10.1021/acs.jpclett.7b01008
M3 - Article
AN - SCOPUS:85021862271
VL - 8
SP - 3040
EP - 3047
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 13
ER -