Two-dimensional Raman-near infrared heterospectral correlation spectroscopy studies of the specific interactions in partially miscible blends of poly(methyl methacrylate) and poly(4-vinylphenol)

2 D Correlation Spectroscopy in Vibrational Spectroscopy

“…4,29,37,43,50,53 -57,64,65,68 -71 Thus, numerous 2D correlation spectroscopy studies have been reported for concentration-or composition-dependent spectral variations of proteins, 29,43,50,57,70 polymers 37,53,54,56,64,65,68,69,71 and multicomponent mixtures. 4,55 For example, systematic studies of polymer blends and copolymers exhibiting specific interactions of components using 2D IR, 2D NIR, 2D Raman and hetero-correlation analysis have been reported.…”

“…Figure 49(a) and (b) shows FT-Raman and NIR spectra of PMMA and its blends with PVPh of contents 5 and 10 wt% in the ranges of 1770-1570 cm 1 and 7500-6500 cm 1 , respectively. 71 In these regions key bands for the specific interactions in the partially miscible blends may be observed. A Raman band at 1729 cm 1 is due to the free CDO stretching mode of PMMA, and a band at 1614 cm 1 , whose intensity increases with the increase in the PVPh content, is readily assigned to the aromatic ring stretching mode of PVPh.…”

“…Raman spectroscopy may now be used with similar success alongside mid-IR and NIR spectroscopy with 2D correlation spectroscopy. 61 -65,68 -71 In an analogous manner as with mid-IR and NIR spectroscopy, 2D Raman correlation spectroscopy has been utilized in the research of transient phenomena, 61,62 molecules, 63 polymers, 64,65,68,69,71 and proteins. 70 Hetero-spectral correlation analysis including Raman spectroscopy has also seen keen interest.…”

“…The Raman-NIR hetero-correlation analysis revealed the presence of a Raman band at 1706 cm 1 for the hydrogenbonded CDO of PMMA and an NIR band at 6764 cm 1 for the hydrogen-bonded OH of PVPh. Ren et al 71 concluded that the two bands are involved in the specific interaction between PMMA and PVPh that is responsible for the partial miscibility of the blends.…”

“…4,55 For example, systematic studies of polymer blends and copolymers exhibiting specific interactions of components using 2D IR, 2D NIR, 2D Raman and hetero-correlation analysis have been reported. 37,53,54,56,64,65,68,69,71 The 2D correlation of concentration-dependent spectral variations gives interesting results for chemical systems where Beer's law does not strictly hold. In other words, if the systems yield nonlinear responses of spectral intensities to concentration changes, some new features would be extracted from 2D correlation analysis.…”