Limits...
Two-dimensional correlation spectroscopy in polymer study.

Park Y, Noda I, Jung YM - Front Chem (2015)

Bottom Line: This review outlines the recent works of two-dimensional correlation spectroscopy (2DCOS) in polymer study. 2DCOS is a powerful technique applicable to the in-depth analysis of various spectral data of polymers obtained under some type of perturbation.The powerful utility of 2DCOS combined with various analytical techniques in polymer studies and noteworthy developments of 2DCOS used in this field are also highlighted.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Kangwon National University Chunchon, South Korea.

ABSTRACT
This review outlines the recent works of two-dimensional correlation spectroscopy (2DCOS) in polymer study. 2DCOS is a powerful technique applicable to the in-depth analysis of various spectral data of polymers obtained under some type of perturbation. The powerful utility of 2DCOS combined with various analytical techniques in polymer studies and noteworthy developments of 2DCOS used in this field are also highlighted.

No MeSH data available.


Synchronous (A) and asynchronous (B) 2D correlation spectra in the first-stage reaction process and synchronous (C) and asynchronous (D) 2D correlation spectra in the second-stage reaction process of the NiPAAm gelation process at 22°C. The solid and dashed lines represent positive and negative cross peaks, respectively. (Reproduced with permission Macromolecules 2013, 46, 3587–3602, Copyright 2013, American Chemical Society).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4356163&req=5

Figure 5: Synchronous (A) and asynchronous (B) 2D correlation spectra in the first-stage reaction process and synchronous (C) and asynchronous (D) 2D correlation spectra in the second-stage reaction process of the NiPAAm gelation process at 22°C. The solid and dashed lines represent positive and negative cross peaks, respectively. (Reproduced with permission Macromolecules 2013, 46, 3587–3602, Copyright 2013, American Chemical Society).

Mentions: Park et al. reported the mechanism of chemical gelation process of poly(N-isopropylacrylamide) (PNiPAAm) hydrogel by using in situ observations with time-resolved FTIR and 2DCOS at two characteristic preparation temperatures below and above the lower critical solution temperature (LCST) of PNiPAAm aqueous solution (Park et al., 2013). Figures 4A,B show the FTIR spectra in the 1800-1050 cm−1 region for the NiPAAm gelation process measured at Tp = 22 and 38°C, respectively. The spectral changes during the NiPAAm gelation process at the two different temperatures were qualitatively similar except for the differences associated with the time required for completing the gelation reaction (~30 and ~15 min at Tp = 22 and 38°C, respectively). The bands at 1628 (Figure 4A) and 1630 cm−1 (Figure 4B) started to appear at ~20 and ~8 min after the onset of the reaction, respectively. Those bands became increasingly remarkable with time and most prominent at the end of the gelation process, independent of Tps. It identifies the specific time-spans for two stage reaction process: the first-stage giving rise to linear and branched random copolymers of NiPAAm and cross-linker monomers and the second-stage giving rise to cross-linking into macroscopic network structure. 2DCOS was thus applied both the first-stage and second-stage reaction processes to better elucidate the gelation process. The each stage of 2D correlation spectra for the NiPAAm gelation process at 22 and 38°C, respectively, shown in Figures 5, 6 are completely different, although IR spectra obtained below and above LCST are apparently similar. From the analysis of 2D correlation spectra, they firstly identified the specific time span for each stage of the two-stage reaction process at two temperatures. Two different gelation process below and above LCST are summarized in Tables 1, 2.


Two-dimensional correlation spectroscopy in polymer study.

Park Y, Noda I, Jung YM - Front Chem (2015)

Synchronous (A) and asynchronous (B) 2D correlation spectra in the first-stage reaction process and synchronous (C) and asynchronous (D) 2D correlation spectra in the second-stage reaction process of the NiPAAm gelation process at 22°C. The solid and dashed lines represent positive and negative cross peaks, respectively. (Reproduced with permission Macromolecules 2013, 46, 3587–3602, Copyright 2013, American Chemical Society).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4356163&req=5

Figure 5: Synchronous (A) and asynchronous (B) 2D correlation spectra in the first-stage reaction process and synchronous (C) and asynchronous (D) 2D correlation spectra in the second-stage reaction process of the NiPAAm gelation process at 22°C. The solid and dashed lines represent positive and negative cross peaks, respectively. (Reproduced with permission Macromolecules 2013, 46, 3587–3602, Copyright 2013, American Chemical Society).
Mentions: Park et al. reported the mechanism of chemical gelation process of poly(N-isopropylacrylamide) (PNiPAAm) hydrogel by using in situ observations with time-resolved FTIR and 2DCOS at two characteristic preparation temperatures below and above the lower critical solution temperature (LCST) of PNiPAAm aqueous solution (Park et al., 2013). Figures 4A,B show the FTIR spectra in the 1800-1050 cm−1 region for the NiPAAm gelation process measured at Tp = 22 and 38°C, respectively. The spectral changes during the NiPAAm gelation process at the two different temperatures were qualitatively similar except for the differences associated with the time required for completing the gelation reaction (~30 and ~15 min at Tp = 22 and 38°C, respectively). The bands at 1628 (Figure 4A) and 1630 cm−1 (Figure 4B) started to appear at ~20 and ~8 min after the onset of the reaction, respectively. Those bands became increasingly remarkable with time and most prominent at the end of the gelation process, independent of Tps. It identifies the specific time-spans for two stage reaction process: the first-stage giving rise to linear and branched random copolymers of NiPAAm and cross-linker monomers and the second-stage giving rise to cross-linking into macroscopic network structure. 2DCOS was thus applied both the first-stage and second-stage reaction processes to better elucidate the gelation process. The each stage of 2D correlation spectra for the NiPAAm gelation process at 22 and 38°C, respectively, shown in Figures 5, 6 are completely different, although IR spectra obtained below and above LCST are apparently similar. From the analysis of 2D correlation spectra, they firstly identified the specific time span for each stage of the two-stage reaction process at two temperatures. Two different gelation process below and above LCST are summarized in Tables 1, 2.

Bottom Line: This review outlines the recent works of two-dimensional correlation spectroscopy (2DCOS) in polymer study. 2DCOS is a powerful technique applicable to the in-depth analysis of various spectral data of polymers obtained under some type of perturbation.The powerful utility of 2DCOS combined with various analytical techniques in polymer studies and noteworthy developments of 2DCOS used in this field are also highlighted.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Kangwon National University Chunchon, South Korea.

ABSTRACT
This review outlines the recent works of two-dimensional correlation spectroscopy (2DCOS) in polymer study. 2DCOS is a powerful technique applicable to the in-depth analysis of various spectral data of polymers obtained under some type of perturbation. The powerful utility of 2DCOS combined with various analytical techniques in polymer studies and noteworthy developments of 2DCOS used in this field are also highlighted.

No MeSH data available.