Demonstrating the Feasibility of Monitoring the Molecular-Level Structures of Moving Polymer/Silane Interfaces during Silane Diffusion Using SFG
- 13 January 2004
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 126 (4), 1174-1179
- https://doi.org/10.1021/ja0390911
Abstract
In this paper, the feasibility of monitoring molecular structures at a moving polymer/liquid interface by sum frequency generation (SFG) vibrational spectroscopy has been demonstrated. N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane (AATM, NH2(CH2)2NH(CH2)3Si(OCH3)3) has been brought into contact with a deuterated poly(methyl methacrylate) (d-PMMA) film, and the interfacial silane structure has been monitored using SFG. Upon initial contact, the SFG spectra can be detected, but as time progresses, the spectral intensity changes and finally disappears. Additional experiments indicate that these silane molecules can diffuse into the polymer film and the detected SFG signals are actually from the moving polymer/silane interface. Our results show that the molecular order of the polymer/silane interface exists during the entire diffusion process and is lost when the silane molecules traverse through the thickness of the d-PMMA film. The loss of the SFG signal is due to the formation of a new disordered substrate/silane interface, which contributes no detectable SFG signal. The kinetics of the diffusion of the silane into the polymer have been deduced from the time-dependent SFG signals detected from the AATM molecules as they diffuse through polymer films of different thickness.Keywords
This publication has 11 references indexed in Scilit:
- Solvent Vapor Induced Ordering and Disordering of Phenyl Side Branches at the Air/Polystyrene Interface Studied by SFGLangmuir, 2002
- STUDIES OF POLYMER SURFACES BY SUM FREQUENCY GENERATION VIBRATIONAL SPECTROSCOPYAnnual Review of Physical Chemistry, 2002
- Correlation of molecular orientation with adhesion at polystyrene/solid interfacesChemical Physics Letters, 2002
- Water at Hydrophobic Surfaces: Weak Hydrogen Bonding and Strong Orientation EffectsScience, 2001
- A FTIR–ATR study of liquid diffusion processes in PET films: comparison of water with simple alcoholsPolymer, 2000
- Sum frequency generation spectroscopy of the aqueous interface: Ionic and soluble molecular solutionsInternational Reviews in Physical Chemistry, 2000
- An attenuated total reflectance cell for analysis of small molecule diffusion in polymer thin films with Fourier-transform infrared spectroscopyPolymer, 1998
- The adhesion promotion mechanism of organofunctional silanesJournal of Applied Polymer Science, 1998
- Designing CD4 immunoadhesins for AIDS therapyNature, 1989
- Silane Coupling AgentsPublished by Springer Nature ,1982