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  • 1
    Electronic Resource
    Electronic Resource
    Novel aspects in the structure of poly(ethylene terephthalate) as revealed by means of small angle x-ray scattering (1991)
    s.l. : American Chemical Society
    Macromolecules 24 (1991), S. 5980-5990 
    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/ma00022a013
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  • 2
    Electronic Resource
    Electronic Resource
    Determination of the interface distribution function of lamellar two-phase systems (1978)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 11 (1978), S. 535-539 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The concept of interface distribution functions [Ruland (1977). Colloid Polym. Sci. 255, 417–427] has been applied to the evaluation of the small-angle scattering of a series of polyethylene samples. The results indicate that the statistics of the lamellar stacking is not necessarily determined by next-neighbor interactions and that non-negligible volume fractions of amorphous domains outside the lamellar systems are observed in a number of samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889878013813
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  • 3
    Electronic Resource
    Electronic Resource
    Small-Angle X-ray Scattering from Blends of PE and SBS. Observation of a Novel Kind of Deviation from Porod's Law (1997)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 30 (1997), S. 708-711 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: In a study of technical blends from poly(ethylene) and poly(styrene)–poly(butadiene) star block copolymers, reproducibility of the blending process and of the structural analysis is tested. A peculiar and reproducible deviation in the angular interval of the scattering curve is observed, which is governed by a decay according to Porod's law. The notion of a faint electron-density undulation in space with a wavelength of 5 nm, an amplitude of 1 e.u. nm−3 and a range of 40 nm could explain the triangular peak observed in a plot which otherwise linearizes the scattering curve in the Porod regime.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889897001556
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    Paper (German National Licenses)
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  • 4
    Electronic Resource
    Electronic Resource
    Studying the Microstructure of Unaged and Aged PVDF by Small- and Wide-Angle X-ray Scattering (1997)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 30 (1997), S. 722-726 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: A layer from plasticized poly(vinylidene fluoride) (PVDF) was aged by exposing one of its faces to an aggressive fluid at elevated temperature and pressure. From visual inspection the aged material appeared not to be homogeneous. Therefore, samples from three distinguishable regions were compared with a sample cut from the virgin material by studying their small- and wide-angle X-ray scattering (SAXS and WAXS). The results show that plasticizer has vanished from the aged material, the crystalline layer thickness distribution has narrowed, amorphous lamellae are collapsed and voids have been created. Within the aged material the number of voids varies: there are more at the inner surface and fewer at the outer surface beneath the rods of a supporting metal grid. Based on the results of this study and theoretical considerations, a method for the quantitative description of the ageing process is proposed, which only requires a simple kind of SAXS measurement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889897001568
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  • 5
    Electronic Resource
    Electronic Resource
    An evaluation method for SAXS-patterns of fibrillar two-phase systems containing oriented particles of moderate anisotropy and short range correlation (1989)
    Springer
    Colloid & polymer science 267 (1989), S. 301-310 
    Details
    ISSN: 1435-1536
    Keywords: SAXS ; orientedfibrils ; blockcopolymers ; drawing ; synchrotronradiation
    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 Starting from the theoretical background of Rulands interface distributions, an evaluation method for small angle x-ray patterns arising from oriented fibrillar two-phase structures is proposed. If the fibril contains highly oriented particles with only moderate anisotropy and if the correlations between those particles within the fibril are of short range only, every axial section of the scattering pattern shows a one dimensional Porod law. A procedure of successive model confinement using the well known tools of nonlinear regression analysis is described. The result of such an analysis for the scattering pattern of an oil diluted SBS block copolymer recorded with synchrotron radiation under first-cycle stretching is reported. Atλ=4 nm four contributions to the scattering pattern could be identified: a) fibrils containing well-defined cylinders standing upright; b) fibrils containing lying cylinders under destruction; c) stretched-out polybutadiene chains, connecting two polystyrene cylinders and causing the observable layer line pattern; and d) stretched-out polybutadiene chains looping through the neighboring PS domain and returning to their starting domain. In addition, a simple method for determining the height-to-diameter ratio of cylinders from the form factor envelope is proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01413623
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  • 6
    Electronic Resource
    Electronic Resource
    The analysis of slightly distorted SAXS layer line patterns from fibrillar two-phase systems with short-range order (1992)
    Springer
    Colloid & polymer science 270 (1992), S. 9-16 
    Details
    ISSN: 1435-1536
    Keywords: SAXS ; layer-line pattern ; drawing ; block copolymers ; synchrotron radiation
    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 information content of small-angle x-ray scattering from fibrillar two-phase systems under strain is discussed. The experimental background is a study of SBS star block copolymer samples during elongation using synchrotron radiation and a two-dimensional detector. The samples exhibit a layer line pattern with the slight indication of a four-point diagram. The theoretical considerations are verified using the experimental data. Special scattering curves (sections and projections) can be extracted from the scattering pattern and are used to describe mathematical peculiarities of the pattern and their physical background. The scope of the paper covers product separability in cylindrical coordinates and an analysis of the separated factors. From the physical point of view information is gained on the validity of the approximation by a “one-dimensional fibrillar system” and the order within bundles of fibrils. An expression is given for the background scattering caused by an ensemble of non-identical oblong particles, organized in bundles of oriented fibrils. The difference in the information on the structure, obtainable from either section or projection, is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00656923
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  • 7
    Electronic Resource
    Electronic Resource
    SAXS investigation on the influence of oil dilution on morphological changes in a SBS block copolymer during the first draw cycle (1989)
    Springer
    Colloid & polymer science 267 (1989), S. 687-701 
    Details
    ISSN: 1435-1536
    Keywords: SAXS ; orientatedfibrils ; blockcopolymers ; drawing ; synchrotronradiation
    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 Spin-cast films of one pure SBS and two oil-extended SBS samples were observed during first cycle drawing in the synchrotron radiation beam at Hasylab. For evaluation, from a two-dimensional Vidicon scattering picture the scattering curve was extracted by intersecting perpendicular to the observed layer lines. Using a method described in a preceding paper [1], the scattering curve is analyzed by fitting to one-dimensional two-phase models. Essential for a fit with parameters of physical sense is the assumption of at least two components. One of these two main components is identified with fibrils containing PS cylinders, the axes of which are orientated parallel; the other is identified with fibrils containing cylinders transverse to the drawing direction. For the mechanical properties of the thermoplastic rubber this splitting of cylinder orientation in the drawn state seems to be of some importance. Only the cylinders of the longitudinal component turn out to be rigid, while the cylinders of the transversal component appear to yield and even break. The amount of cylinders allotted to each of the two components in the drawn state varies as a function of the diluent. An extrapolation of topological parameters back to the undrawn state indicates a possible reason, a fair variation of the cylindrical particle dimensions within a “lattice cell” of only slighly varying dimensions. While paraffinic mineral oil dilution causes the cylinders lengths to decrease, thus improving cylinder orientability within the pseudo lattice cell, aromatic oil dilution increases the particles diameters. A remaining faint contribution to the scattering pattern that produces the layer lines is suggested not to be caused by a periodic structure, but by a single and precisely defined polybutadiene matrix length (“string”) between two PS cylinders with a considerable height variance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01524371
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  • 8
    Electronic Resource
    Electronic Resource
    Morphological changes in SBS block copolymers caused by oil extension as determined by absolute small angle x-ray scattering (1989)
    Springer
    Colloid & polymer science 267 (1989), S. 281-291 
    Details
    ISSN: 1435-1536
    Keywords: Blockcopolymers ; oildilution ; morphology ; phaseseparation ; phasehomogeneity ; absoluteSAXS
    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 series of SBS block copolymers diluted with different amounts (0–60 wt%) of three different kinds of oil were investigated: 1) lithene PM (a low molecular weight polybutadiene); 2) a paraffinic mineral oil with its electron density close to that of the polybutadiene (PB) phase; 3) a highly aromatic mineral oil with an electron density close to the polystyrene (PS) phase. All the oils seem to go into the polybutadiene matrix. Paraffinic oil and lithene form a homogeneous phase with PB; the aromatic oil at low concentrations mixes with the PB phase with a high level of inhomogeneity, while at higher concentration partial phase separation occurs. In the undiluted polymer, styrene forms cylinders in hexagonal packing. The distance between cylinders (about 43 nm) is not significantly changed upon dilution up to 33 wt%. Previously proposed changes in the morphology of PS domains at larger oil contents can be related to observed changes in the long period, in the segment length distributions, and in the homogeneities of the phase (density fluctuations). The electron density difference obtained for pure SBS is lower than the theoretical one calculated from the densities of pure PS and pure PB. Dilution by paraffinic oil improves the phase separation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01413621
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  • 9
    Electronic Resource
    Electronic Resource
    SAXS data analysis of a lamellar two-phase system. Layer statistics and compansion (1993)
    Springer
    Colloid & polymer science 271 (1993), S. 1007-1023 
    Details
    ISSN: 1435-1536
    Keywords: SAXS ; two-phase system ; finite lamellar stacks ; stacking statistics ; PET
    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 An analysis of small angle x-ray scattering (SAXS) data from three injection molded poly(ethylene terephthalate) (PET) samples is carried out. Two of the samples are annealed at different temperatures. The chosen concept of data analysis is that of Ruland's interface distribution function (IDF) of lamellar two-phase systems. The IDF can be expanded into a series of distance distributions, containing the information on the topological properties of the ensemble of lamellar stacks in the semicrystalline sample. The paper describes the stepwise refinement of a topological model. The final model is described by only few parameters of physical meaning. It unifies the well-known concepts of an ensemble of non-uniform stacks, finite stack size and one-dimensional paracrystalline disorder in an analytical expression. In order to deduce this expression, the concept of inhomogeneity (imagine a variation of the long period from stack to stack) is generally treated in terms of “compansion”, a suggested superposition principle. Its mathematical equivalent in one dimension is the Mellin convolution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00659290
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  • 10
    Electronic Resource
    Electronic Resource
    Investigation of molecular order and phase transitions of smectic poly(ester imide)s by means of small-angle X-ray scattering (2000)
    Springer
    Colloid & polymer science 278 (2000), S. 1061-1069 
    Details
    ISSN: 1435-1536
    Keywords: Key words Smectic ; Poly(ester imide)s ; Small-angle X-ray scattering ; Lamellar
    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 molecular order and phase transitions of two smectic poly(ester imide)s based on aminobenzoic acid trimellitimide (PEI 1) or aminocinnamic acid trimellitimide (PEI 2) and α,ω-dihydroxydodecane were investigated by X-ray scattering. During cooling, the polymers pass through monotropic smectic liquid-crystalline (LC) phases (SA, SC), which transform into higher-ordered smectic-crystalline phases (SE, SH). The smectic layer structure of about 3 nm gives rise to a sharp reflection at 2θ ≅ 3°. Peak shape analysis and analysis of the interface distribution function revealed long-range longitudinal correlation among the mesogens in the LC phase but short-range lateral correlation. The development of a broad reflection in the small-angle X-ray scattering (SAXS, 2θ 〈 1°) indicates the formation of a lamellar two-phase system. The long-period changes reversibly between 10 and 30 nm with increasing temperature. The crystalline lamellae comprise a number of smectic-crystalline layers with packed mesogens, while the noncrystalline interlamellar regions keep their smectic-LC order. In the metastable SB phase, formed during annealing of quenched PEI 1, the diffuse SAXS indicates a random distribution of small, probably fringed, crystals with hexagonal-packed mesogens. In the lamellar SE and SH phases, tie molecules play an important role, but chain folding cannot be excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003960000370
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