ANYL 270 |
| Opto-rheology is the measurement of polymer deformation and flow performed simultaneously with spectroscopy. Dynamic infra-red(IR) spectroscopy combines step-scan Fourier transform IR and a synchronized Polymer Modulator which applies a mechanical stress to the polymer film. By recording the applied mechanical stress and resultant strain, the bulk mechanical properties of the polymer film can be determined. Simultaneously, the dynamic changes to the infra-red spectrum of the polymer are recorded and provide molecular information. Dynamic IR spectroscopy can be used to correlate the macroscopic properties of polymers with the structural changes at the molecular level during an applied perturbation (stretch) of the polymer. The bulk mechanical (dynamic mechanical analysis) and opto-rheological properties of several poly(p-phenylene vinylene)(PPV) and PPV derivatives have been characterized. An example of the ability of dynamic infrared spectroscopy to distinguish and successfully identify phenylene ring stretches along a polymer backbone from ring stretches associated with a phenoxy subsitutent will be illustrated by poly(2-phenoxy p-phenylene vinylene). Dynamic IR was crucial in making the proper assignments in the phenylene ring region. Spectral analysis involves in-phase and quadrature spectra along with two-dimensional IR correlation maps. Assignments were supported by density functional theory (DFT) calculations and validate the interpretations made based on dynamic IR spectroscopy. |
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Analytical Approaches, Spectroscopy
8:30 AM-12:00 PM, Wednesday, 13 September 2006 Moscone Center -- Room 124, Oral
Division of Analytical Chemistry |