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  • 1
    Electronic Resource
    Electronic Resource
    Small-angle x-ray investigation of morphological order in the system: isotactic polystyrene-poly(2,6-dimethylphenylene oxide) (1986)
    s.l. : American Chemical Society
    Macromolecules 19 (1986), S. 1272-1274 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00158a059
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  • 2
    Electronic Resource
    Electronic Resource
    Morphological Studies of Semicrystalline Poly(2,6-dimethylphenylene oxide) (1976)
    s.l. : American Chemical Society
    Macromolecules 9 (1976), S. 253-257 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma60050a015
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  • 3
    Electronic Resource
    Electronic Resource
    The influence of molecular weight and mould temperature on the skin-core morphology in injection-moulded polypropylene parts containing weld lines (1996)
    Springer
    Journal of materials science 31 (1996), S. 2487-2493 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The sandwich structure of injection-moulded polypropylene parts with and without weld lines has been investigated using optical microscopy. X-ray scattering, and differential scanning calorimetry. It was found that the skin-layer thickness is strongly dependent on whether the mould is injected through one gate or through two gates. Samples containing a weld line show a much lower skin-layer thickness than samples without a weld line. This difference, however, depends strongly on the molecular weight of the polypropylene. The skin-layer thickness also varies along the flow path and decreases with increasing mould temperature. While most of the polypropylene crystallizes in the crystallographic α-modification, in the textured skin layer, some β-modification occurs. The β-crystallinity depends on the molecular weight but disappears in the weld line. X-ray investigations exhibited a bimodal crystal orientation in the skin layer, one with thec-axis oriented parallel to the flow direction, the second one with thea *-axis oriented parallel to the flow direction. The core exhibited only a weakc-axis orientation. In the skin, the metastable α1-modification was found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01152966
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  • 4
    Electronic Resource
    Electronic Resource
    Molecular fractionation in isotactic polypropylene during isothermal crystallization (1998)
    Springer
    Colloid & polymer science 276 (1998), S. 747-749 
    Details
    ISSN: 1435-1536
    Keywords: Key words Polypropylene ; nucleation ; isothermal crystallization ; molecular fractionation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The nucleation frequency of isotactic polypropylene shows for certain molecular weight distributions during isothermal crystallization a “stepwise” development of the nuclei as a function of time. The resulting curve can be fitted by a superposition of exponential functions assuming a separate nucleation density for each nucleation step. The multimodal nucleation is discussed as a consequence of molecular fractionation effects during crystallization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003960050013
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  • 5
    Electronic Resource
    Electronic Resource
    Small angle X-ray studies on the core crystals in oriented polypropylene/polybutene-1 blends (1984)
    Springer
    Colloid & polymer science 262 (1984), S. 435-444 
    Details
    ISSN: 1435-1536
    Keywords: core-fibrils ; polypropylene/polybutene-1 blends ; small-angle x-ray scattering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The equatorial small-angle x-ray scattering of blends of polypropylene and polybutene-1 crystallized from the oriented melt, has been analyzed by means of Guinier- and Porod analysis and absolute intensity measurements. The thickness of the core crystals, which appear to have an ellipsoidal shape, is of the order of 160 Å and does not vary with sample composition. Measurements of the half widths of the (110)- and (220)-wide angle x-ray diffraction lines indicate a decrea.se of the lateral dimension of the core crystals for both components. Calculations of the scattering power through a three-phase model for the electron densities indicate a non-proportional distribution of crystalline and amorphous phases in the blends.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01412037
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  • 6
    Electronic Resource
    Electronic Resource
    Application of interface distribution functions to the evaluation of the small angle x-ray scattering of multicomponent polymer systems (1989)
    Springer
    Colloid & polymer science 267 (1989), S. 389-398 
    Details
    ISSN: 1435-1536
    Keywords: Interface distribution function ; small angle x-ray scattering ; polymer blends.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A method for correcting the small angle x-ray intensity of multi-component polymer systems to compute the interface distribution function is presented. The resolution of this function can be improved to a great extent by evaluating the interference function from the measured intensity corrected for fluctuation scattering by use of a function which is proportional to the gas scattering of the investigated system. The method is applied successfully to polymer blends composed of components having similar morphology.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410183
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  • 7
    Electronic Resource
    Electronic Resource
    Optical properties and structure of drawn polyethyleneterephtalate-polyethylene films (1982)
    Springer
    Colloid & polymer science 260 (1982), S. 31-36 
    Details
    ISSN: 1435-1536
    Keywords: PET/PE ; Specular Reflection ; Optical Properties ; Structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Films made by coextrusion of polyethyleneterephtalate and low density polyethylene exhibit specular reflection of light when stretched. Unlike the behaviour of films made of pure PET, where specular reflection is rare and does occur at extremely high stretching rates only, PET/LDPE films show specular reflection independent of the stretching rate. A film, containing 70% PET and 30% LDPE, prepared by coextrusion of the two components, has been investigated by scanning electron microscopy, light microscopy and by measuring the optical properties with a spectrophotometer. The (unstretched) „as prepared“ sample has been compared with a sample stretched to λ=4. The optical measurements show as a result of the stretching a strong decrease of the transmittance and an increase of the remittance. While there is no drastic change of the dispersion (which is only slight), the increase of the refractive index indicates some straininduced crystallization. The scanning electron micrographs show long, needlelike voids and indicate a fractionation of the two components as a result of the stretching. This fractionation has been investigated by heating the samples up under the light microscope: while the stretched sample shows a separation of the components, the unstretched sample does not.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01447673
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  • 8
    Electronic Resource
    Electronic Resource
    Analysis of the small-angle X-ray scattering of linear polyethylene by a paracrystalline lattice model (1983)
    Springer
    Colloid & polymer science 261 (1983), S. 293-298 
    Details
    ISSN: 1435-1536
    Keywords: small angle X-ray scattering ; model calculations ; paracrystal ; polyethylene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Three paracrystalline lattice models for the interpretation of the small angle scattering of polyethylene are discussed: The “lattice model”, the “stapel model” (often referred to as the lamellar stack model) and the “proportional model”. While the applicability of the first model is restricted, the latter models differ in the statistical assumptions of lamellar and interlamellar thickness distributions. The principal advantage of the proportional model over the stapel model is its applicability through the adjustment of only three parameters: long period, crystallinity and one statistical parameter. Small angle X-ray curves of linear polyethylene are interpreted by the proportional model. The results are in good agreement with stapel model calculations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01413934
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  • 9
    Electronic Resource
    Electronic Resource
    Interactions between the components in isotactic polypropylene blended with EPDM (1993)
    Springer
    Colloid & polymer science 271 (1993), S. 824-833 
    Details
    ISSN: 1435-1536
    Keywords: Polypropylene ; EPDM ; interphase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The interaction of isotactic polypropylene with ethylene propylene diene terpolymer in their blends has been investigated by use of differential scanning calorimetry, dynamic mechanical analysis, wide- and small-angle x-ray scattering, and by investigating the nucleation and kinetics of crystallization of the iPP component under the polarization microscope. It is found, that the dispersion of the EPDM component in the iPP matrix is dependent on blend composition and is maximal at 10% EPDM content. An interface layer between the two components is formed by migration of iPP molecules into the EPDM phase. A model for this interface is proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00652764
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  • 10
    Electronic Resource
    Electronic Resource
    Die Bedeutung der mittleren Probendichte für die quantitative Interpretation der Röntgenkleinwinkelstreuung teilkristalliner Polymerer (1978)
    Springer
    Colloid & polymer science 256 (1978), S. 125-132 
    Details
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Summary Superstructural parameters of polymeric material composed of clusters of lamella-shaped crystals can be obtained by model-calculations of their small-angle x-ray scattering curves. In this paper it has been demonstrated, that in many cases the modulation of the scattering curve is determined not only by the inner structure of the cluster but also dependent on the average (electron) density of the cluster environment, the mean sample density. Discussing the SAXS of the systems HDPE, PP and iPS/PPO it has been shown, that the use of a simpler „,black-white” model, in which the crystalline density has been setϱ c = 1 and the amorphous densityϱ a = 0, leads to a „phony fit”. The incorporation of the mean sample density into the model yields a different set of parameters. The mean sample density can be neglected as soon as the number of lamellae per cluster exceeds the value of 10.
    Notes: Zusammenfassung Die Bestimmung von überstrukturdaten polymerer Lamellenclustersysteme kann über Modellrechnungen der Röntgenkleinwinkelstreukurven erfolgen. Es wird gezeigt, daß in vielen Fällen die Modulation der Streukurve nicht allein durch die innere Struktur der Cluster bestimmt ist, vielmehr muß die mittlere Elektronendichte der Umgebung der Cluster mitberücksichtigt werden. An den Systemen HDPE, PP und iPS/PPO wird gezeigt, daß die Verwendung eines einfacheren Modells, in dem die kristalline Dichte ϱc = 1 und die amorphe Dichte ϱa = 0 gesetzt wird („schwarzweiß”-Modell), für kleine Lamellenzahlen pro Cluster zu einer Scheinanpassung führt. Die BerÜcksichtigung der mittleren Probendichte fÜhrt zu abweichenden Anpassungsparametern bei der Berechnung der experimentellen Streukurve und damit zu anderen Über-rstrukturdaten. Der Einfluß der Umgebungsdichte wird vernachlässigbar klein, wenn die Zahl der lagekorrelierten Lamellen pro Cluster größer als 10 wird.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01679169
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