Journal ArticleDOI
Wide-Angle X-ray Diffraction Study of the Phase Behavior of Vinyl Alcohol-Ethylene Copolymers
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In this paper, the influence of the composition and thermal history on the type of lattice developed has been studied by wide-angle X-ray diffraction measurements in three vinyl alcohol−ethylene, VAE, copolymers with different compositions, which were crystallized from the melt at various cooling rates.Abstract:
The influence of the composition and thermal history on the type of lattice developed has been studied by wide-angle X-ray diffraction measurements in three vinyl alcohol−ethylene, VAE, copolymers with different compositions, which were crystallized from the melt at various cooling rates. The results are compared with those of the corresponding homopolymers, poly(vinyl alcohol) and low-density polyethylene. Both the composition and the cooling rate have been found to determine the crystalline structure of these VAE copolymers. Thus, for the samples slowly crystallized from the melt, a monoclinic lattice is obtained for copolymers VAE71 and VAE68 (with compositions of 71 and 68 mol % VA, respectively) while an orthorhombic lattice has been found for copolymer VAE56 (56 mol % VA). The effect of the cooling rate is very important, since copolymers VAE71 and VAE68 lead to the orthorhombic form when the samples are quenched from the melt. Copolymer VAE56 has been found to crystallize in an orthorhombic lattice...read more
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Effect of crosslinking on the mechanical and thermal properties of poly(vinyl alcohol)
TL;DR: In this article, a broad range of degrees of crosslinking, from 1.7 up to 74% of reacted hydroxyl groups, was achieved, and the variation of the thermal and mechanical properties of PVA with the crosslink density show an initial decrease due to the diminution of the crystallinity of the system, caused by the cross-linking.
Journal ArticleDOI
Ethylene vinyl alcohol: a review of barrier properties for packaging shelf stable foods.
K. Khanah Mokwena,Juming Tang +1 more
TL;DR: The aim of this review is to give an overview of research on the oxygen barrier properties of EVOH from the perspective of structure-barrier property relationships and the consequences of food processing conditions.
Journal ArticleDOI
Development of EVOH-kaolinite nanocomposites
TL;DR: In this article, a novel route to develop EVOH-kaolinite nanocomposites by a melt intercalation process and on some relevant nanocompositionite properties as a function of composition was reported.
Journal ArticleDOI
Self‐Sterilized EVOH‐TiO2 Nanocomposites: Interface Effects on Biocidal Properties
María L. Cerrada,Cristina Serrano,Manuel Sánchez-Chaves,Marta Fernández-García,Fernando Fernández-Martín,Alicia de Andrés,Rafael J. Jiménez Riobóo,Anna Kubacka,Manuel Ferrer,Marcos Fernández-García +9 more
TL;DR: In this article, the structural characteristics of the nanocomposites were examined using wide and small angle X-ray scattering (WAXS/SAXS), and vibrational infrared and Raman spectroscopy.
Journal ArticleDOI
Morphological Alterations Induced by Temperature and Humidity in Ethylene−Vinyl Alcohol Copolymers
Amparo López-Rubio,Jose M. Lagaron,Enrique Giménez,David Cava,Pilar Hernández-Muñoz,Tomoyuki Yamamoto,Rafael Gavara +6 more
TL;DR: In this paper, the morphologies of a number of high barrier ethylene−vinyl alcohol food packaging films with different ethylene contents have been evaluated by simultaneous WAXS/SAXS, FT-IR, DSC, and Raman spectroscopy.
References
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Journal ArticleDOI
General procedure for evaluating amorphous scattering and crystallinity from X-ray diffraction scans of semicrystalline polymers
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Journal ArticleDOI
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Journal ArticleDOI
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Journal ArticleDOI
Role of mobile phases in the crystallization of polyethylene. Part 1. Metastability and lateral growth
TL;DR: In this article, it was shown that all polyethylene growth occurs in the hexagonal phase, and only in this phase, irrespective of whether in hexagonal (h) or orthorhombic (0) stability regime of P-T phase diagram.
Journal ArticleDOI
A Raman spectroscopic study of the morphological structure of the polyethylenes
M. Glotin,L. Mandelkern +1 more
TL;DR: The method described by Strobl and Hagedorn to analyze the Raman spectrum internal modes of semi-crystalline polyethylene has been applied to a set of selected polymethylene samples crystallized under controlled conditions as discussed by the authors.