Absolute local conformation of poly(methyl methacrylate) chains adsorbed on a quartz surface

Polymer chains at a buried interface with an inorganic solid play a critical role in the performance of polymer nanocomposites and adhesives. Sum frequency generation (SFG) vibrational spectroscopy with a sub-nanometer depth resolution provides valuable information regarding the orientation angle of...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of chemical physics 2023-12, Vol.159 (24)
Main Authors: Kawaguchi, Daisuke, Sasahara, Kazuki, Inutsuka, Manabu, Abe, Tatsuki, Yamamoto, Satoru, Tanaka, Keiji
Format: Article
Language:English
Subjects:
Functional groups
Molecular conformation
Molecular dynamics
Nanocomposites
Nonlinear optics
Physics
Polymers
Polymethyl methacrylate
Quartz
Solid surfaces
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Polymer chains at a buried interface with an inorganic solid play a critical role in the performance of polymer nanocomposites and adhesives. Sum frequency generation (SFG) vibrational spectroscopy with a sub-nanometer depth resolution provides valuable information regarding the orientation angle of functional groups at interfaces. However, in the case of conventional SFG, since the signal intensity is proportional to the square of the second-order nonlinear optical susceptibility and thereby loses phase information, it cannot be unambiguously determined whether the functional groups face upward or downward. This problem can be solved by phase-sensitive SFG (ps-SFG). We here applied ps-SFG to poly(methyl methacrylate) (PMMA) chains in direct contact with a quartz surface, shedding light on the local conformation of chains adsorbed onto the solid surface. The measurements made it possible to determine the absolute orientation of the ester methyl groups of PMMA, which were oriented toward the quartz interface. Combining ps-SFG with all-atomistic molecular dynamics simulation, the distribution of the local conformation and the driving force are also discussed.
ISSN:0021-9606
1089-7690
DOI:10.1063/5.0184315