Raman spectroscopic study of conformational changes in the amorphous phase of poly(lactic acid) during deformation

Raman microspectroscopy study of structure, dispersibility, and crystallinity of poly(hydroxybutyrate)/poly(l-lactic acid) blends

“…Therefore, Raman spectroscopy has been used to elucidate the crystalline/amorphous structure, molecular interactions, and conformations of polymers [26][27][28][29][30][31][32]. Raman spectra of polymers show many bands due to skeletal deformation modes in the low frequency region.…”

“…Yang et al investigated the rotational isomeric states, i.e. trans or gauche conformation, of PLLA by comparing experimental Raman spectra of PLLA with simulated ones derived from normal coordinate analysis [28,31]. Their results suggested that PLLA has the tgt conformation.…”

Morphological Study on Thermal Shrinkage and Dimensional Stability Associated with Oriented Poly(lactic acid)

“…Our prior study shows that the deformation of amorphous PLA films increases the tg′t population, thereby facilitating strain-induced crystallization. 9 The present work uses the same spectroscopic technique on PLA fibers and relates the amorphous chain deformation to macroscopic thermal shrinkage. Differential scanning calorimetric data reveal two distinct types of amorphous regions in drawn PLA fibers.…”

Perturbing effects of bulky comonomers on the chain conformation of poly(vinylidene fluoride)

“…The Raman intensities were calculated using a simple bond polarizability model [30,31,34,38]. For PVDF homopolymer and P(VDFeHFP) copolymer, the bond polarizability model includes contributions from seven sets of coordinates.…”

“…These modes are easy to measure and can be simulated using bond polarizability model [34,38,41]. The molecular structural parameters used in this study are shown below: the CeH, CeF and CeC bonds used were 1.096 Å , 1.34 Å and 1.54 Å , respectively.…”