Poly FTIR difference spectra

To simplify the synthetic effort required to deposit such films, attempts were made to deposit films by pyrolyzing tetrafluoro-p-xylene (F4C8H6). Under similar reaction conditions, a polymer film was deposited that was different from poly(tetrafluoro-p-xylylene) as the FTIR spectrum indicates that it contains more hydrogen and less fluorine. Presumably HF is preferentially eliminated rather than H2. 

Figure 4.38. (a) IR ATR microscopic spectra of clean hair (solid line) and hair-sprayed hair (dashed line), (b) Difference specfrum (solid line) and reference spectrum of poly(vinylacefafe) (dashed line). Spectra were measured with Nic-Plan microscope interfaced to Magna-IR (Nico-let Instrument Corp.) FTIR spectrometer. Sixty-four sample scans at resolution of 8cm were coadded and rationed against 64 background scans. Reprinted, by permission, from P. A. Martoglio, Nicolet Application Note, AN-9694, Nicolet Instrument, Madison, 1997. Copyright Nicolet Instrument Corp. 

There are quite a number of differences between the FTIR spectrum of cw-polyacetylene and tran -poly-... 

Ozaki et al. [106] studied blends of poly(R)-3-hydroxybutyrate) (PHB) and PLLA using FTIR microspectroscopy, and showed that crystalline bands were observed due to PHB, whereas those due to PLLA were hardly observed for all PHB/PLLA blends investigated. On the other hand, some crystalline bands of PLLA were observed in the microinfrared spectra of some spots in the 20/80 PHB-co-HHx/ PLLA blend. Microinfrared spectra also showed a significant difference in the compatibility and crystalline structures between the PHB-co-HHx/PLLA and PHB/PLLA blends. Figure 20.25a and b show microinfrared spectra in the 2000-1000cm region of PHB/PLLA and PHB-co-HHx/PLLA blends with 80/20 and 20/80 blending ratios. The differences in the infrared spectra between neat PHB and PHB-co-HHx lie mainly in the intensities of the crystalline and amorphous bands. The ratios of peak intensities of PHB and PLLA bands were dependent on the measurement points in both blends. In the 80/20 PHB/PLLA blend, the spectra of many spots were similar to the crystalline PHB spectrum, but the main... 

FIGURE 4.19 An example of an FTIR spectrum for three different example polymers poly(vinyl pyridine) (P4VP), polystyrene, and a poly(vinyl pyridine)-block-polystyrene (PS-b-P4VP). In the data shown, we can clearly see that the block copolymer has characteristics of both of its individual polymer block components. The C=C stretch mode is visible at about 1500 cm" for all three molecules. 

In order to determine the polymer chain orientation, infrared measurements of transmittance or absorbance must be performed with polarized IR radiation, parallel or perpendicular to the mechanical draw direction, for a particular absorption band of the spectrum. Fig. 7.11 shows the FTIR spectra obtained for two orthogonal polarization directions, parallel and perpendicular to the draw direction of a poly(vinylidene fluoride) (PVDF) polymer sample. It is possible to observe that the overall spectra are similar with neither modes being totally suppressed nor new modes seeming to appear. Nevertheless, the amount of IR radiation absorbed by some particular modes are clearly different for IR spectra obtained with radiation polarized in the perpendicular or parallel to the polymer draw direction (Fig. 7.11). 

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