The present study is aimed at investigating structure, dispersibility, and crystallinity of poly(3-hydroxybutyrate) (PHB) and poly(l-lactic acid) (PLLA) blends by using FT-IR microspectroscopy and differential scanning calorimetry (DSC) Four kinds of PHB/PLLA blends with a PLLA content of 20, 40, 60, and 80 wt % were prepared from chloroform solutions Micro-IR spectra obtained at different positions of a PHB film are all very similar to each other, suggesting that there is no discernible segregated amorphous and crystalline parts on the PHB film at the resolution scale of micro-IR spectroscopy On the other hand, the micro-IR spectra of two different positions of a PLLA film, where spherulite structures are observed and they are not observed, are significantly different from each other PHB and PLLA have characteristic IR marker bands for their crystalline and amorphous components Therefore, it is possible to explore the structure of each component in the PHB/PLLA blends by using micro-IR spectroscopy

Structure, Dispersibility, and Crystallinity of Poly(hydroxybutyrate)/Poly(l-lactic acid) Blends Studied by FT-IR Microspectroscopy and Differential Scanning Calorimetry

Infrared (IR) spectra of new types of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx = 2.5, 3.4, and 12 mol %), and poly(3-hydroxybutyrate) (PHB) were measu...

Infrared spectroscopy studies of CH...O hydrogen bondings and thermal behavior of biodegradable poly(hydroxyalkanoate)

The purpose of this review article is to outline recent progress in near-infrared (NIR) spectroscopy. Some particular emphasis is put on the delineation of its versatility in analytical chemistry. NIR spectroscopy is versatile in many aspects. For example, it is electronic spectroscopy as well as vibrational spectroscopy. It is also all-round in applications from basic to practical applications. NIR spectroscopy can be applied to various kinds of materials, bulk materials, thin or thick polymers, tablets, human bodies, and so on. It is particularly powerful in non-invasive, non-destructive, and in situ analysis. In this review, the principles and advantages of NIR spectroscopy are described first, and then its applications to various fields, including polymer science, on-line monitoring, inorganic material research, medical diagnosis, and NIR imaging are introduced.

https://www.jstage.jst.go.jp/article/analsci/28/6/28_545/_pdf

Near-infrared spectroscopy--its versatility in analytical chemistry.

Infrared and Raman spectroscopy and quantum chemistry calculation studies of C–H⋯O hydrogen bondings and thermal behavior of biodegradable polyhydroxyalkanoate

Reducing the formation of six-membered ring ester during thermal degradation of biodegradable PHBV to enhance its thermal stability

The thermal behavior and molecular interaction of a new type of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx = 12 mol %), was investigated by using wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The WAXD measurements were carried out over a temperature range from 25 to 110 °C in the scattering angle range of 2θ = 5−13°. The WAXD pattern at room temperature shows that the P(HB-co-HHx) copolymer has an orthorhombic system (α = β = γ = 90°) with a = 5.76 A, b = 13.20 A, and c = 5.96 A (fiber repeat), which is identical to the crystal system of poly(3-hydroxybutyrate) (PHB) homopolymer. However, temperature-dependent variations in the lattice parameters, a and b, of P(HB-co-HHx) are quite different from those of PHB. Only the a lattice parameter increases with temperature, while the b lattice parameter changes very little in the case of crystalline P(HB-co-HHx). It seems that the intermolecular and intramolecular interactions between...

Hartuni Sato

Papers

Thermal Behavior and Molecular Interaction of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) Studied by Wide-Angle X-ray Diffraction