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Highlights: [•] The glass transition point of PVC was advanced by addition of FeCl2. [•] FeCl2 caused an earlier degradation and a more effective degradation of PVC. [•] FeCl2 changed the degradation products of PVC. [Copyright &y& Elsevier]

Abstract: The thermal behaviors of homologues, derivatives and adducts of β-cyclodextrin (β-CD) are compared based on thermogravimetry (TG) and gas chromatography coupled to time-of-flight mass spectrometry (GC–TOF-MS) analysis. Our results indicate that the number of glucose units and the introduced groups cause a considerable change in thermal decomposition mechanisms of these carbohydrates. Further, it is observed that the mass loss of the bicomponent aggregate formed by phenylarsonic acid (PAA) and β-CD is larger than that of each of the components at higher temperatures. Additionally, the decomposition of the adduct produces a series of arsenic compounds with high relative abundances, such as AsO+, As2O2 +, As3O4 + and As4O6 +, which is rather different from the decomposition behaviors of free PAA and the adduct of β-CD with sodium arsenite. [ABSTRACT FROM AUTHOR]

Abstract: The thermal decomposition behavior of survived β-cyclodextrin in its inclusion complex of clove oil is investigated by nonisothermal thermogravimetry (TG) analysis at the heating rates of 5.0, 10.0, 15.0, 20.0 and 25.0Kmin−1. The TG profiles based on mass loss as a function of temperature show a clear trend of increased thermal decomposition temperature with increased heating rate. Gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS) with a programmed temperature heating treatment is performed to experimentally investigate the relationship between procedural decomposition temperature and fragment composition of the sample. The results on the basis of fragment analysis explain the different mass loss of the sample corresponding to different temperatures on the gradient hot stage. [Copyright &y& Elsevier]