title: Details of thermal behavior of spin-coated film of biodegradable poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer studied by principal component analysis-based two-dimensional (PCA2D) correlation spectroscopy.
abstract: Principal component analysis-based two-dimensional (PCA2D) correlation spectroscopy was applied to the temperature-dependent infrared-reflection absorption (IRRAS) spectra of a spin-coated film of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)) (HHx=7.2 mol%) copolymer. In asynchronous PCA2D correlation spectra, we clearly captured the existence of two components in the crystalline band of the CO stretching mode, well-ordered primary crystals observed at lower wavenumber and less ordered secondary crystals observed at higher wavenumber, which is not readily detectable in the original 1D spectra. Furthermore, the intensity changes of bands at 1298 and 1280 cm(-1) are significantly different in the temperature ranges below and above the transition temperature around 140 degrees C identified by the 2D first derivatives plot. The result further confirms that the sequence of intensity changes with increasing temperature is such that bands for less ordered crystalline components of P(HB-co-HHx) (HHx=7.2 mol%) are changing first at an earlier (i.e., lower temperature) stage.
authors: Department of Chemistry, Kangwon National University, Chunchon 200-701, Republic of Korea.
authors: Ho
authors: H
authors: Ji
authors: Seung Bin
authors: SB
authors: Kim
authors: Isao
authors: I
authors: Noda
authors: Young Mee
authors: YM
authors: Jung
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000737:chemistry*; D001673:Biodegradation, Environmental; D002208:Caproates / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D008422:Materials Testing; D008567:Membranes, Artificial; D011108:Polymers / Q000737:chemistry; D025341:Principal Component Analysis; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013696:Temperature; D013818:Thermogravimetry; D000094122:Polyhydroxybutyrates
chemical_list: D020155:3-Hydroxybutyric Acid; D002208:Caproates; D020099:Coated Materials, Biocompatible; D008567:Membranes, Artificial; D011108:Polymers; C115940:poly(3-hydroxybutyrate-co-3-hydroxyhexanoate); D000094122:Polyhydroxybutyrates