Temperature-Dependent Crystalline-Amorphous Structures in Isotactic Polypropylene: Small-Angle X-ray Scattering Analysis of Edge-Bounded Two-Phase Systems

1995 ◽  
Vol 28 (15) ◽  
pp. 5267-5273 ◽  
Author(s):  
T. Albrecht ◽  
G. Strobl
Keyword(s):  
Isotactic Polypropylene ◽  
Small Angle ◽  
Temperature Dependent ◽  
Two Phase ◽  
X Ray ◽  
X Ray Scattering ◽  
Amorphous Structures ◽  
Phase Systems ◽  
Ray Scattering

Small-angle X-ray scattering of two-phase systems: significance of polydispersity

2010 ◽  
Vol 43 (5) ◽  
pp. 998-1004 ◽  
Author(s):  
Wilhelm Ruland
Keyword(s):  
Size Distribution ◽  
Small Angle ◽  
Two Phase ◽  
X Ray ◽  
X Ray Scattering ◽  
Phase Systems ◽  
Two Phases ◽  
The Relationship ◽  
Ray Scattering

Evaluation of the small-angle X-ray scattering of two-phase systems leads to the determination of the Porod lengthlpand the correlation lengthlc. In dilute systems, the parameter κl=lc/lp− 1 is a measure of the polydispersity of the chord lengthslwithin the dilute phase, which depends on the size distribution and the shape of the particles forming this phase. As an example, the change of κlwith the size distribution is calculated for spheres and spheroids. For dense two-phase systems, κldepends not only on the polydispersities of the chord lengthsl1andl2of the two phases but also on the spatial order in the system. This is demonstrated by examples related to microemulsions. The appendix contains a short discussion on the relationship between chord-length distributions and Bertrand's paradox.

Small-Angle X-ray Scattering on Two-Phase Systems under Pressure:  Determination of Thermodynamic Parameters

1997 ◽  
Vol 30 (21) ◽  
pp. 6645-6649 ◽  
Author(s):  
M. Lorenzen ◽  
P. Bösecke ◽  
C. Ferrero ◽  
C. Riekel ◽  
A. Eichler
Keyword(s):  
Thermodynamic Parameters ◽  
Small Angle ◽  
Two Phase ◽  
X Ray ◽  
X Ray Scattering ◽  
Phase Systems ◽  
Ray Scattering

Small angle X-ray scattering study of porosity variation in a styrene-divinylbenzene copolymer

1981 ◽  
Vol 46 (7) ◽  
pp. 1675-1681 ◽  
Author(s):  
Josef Baldrian ◽  
Božena N. Kolarz ◽  
Henrik Galina
Keyword(s):  
Small Angle ◽  
Structural Parameters ◽  
Two Phase ◽  
X Ray ◽  
Porosity Variation ◽  
Swelling Agent ◽  
X Ray Scattering ◽  
Styrene Divinylbenzene ◽  
Ray Scattering

Porosity variations induced by swelling agent exchange were studied in a styrene-divinylbenzene copolymer. Standard methods were used in the characterization of copolymer porosity in the dry state and the results were compared with related structural parameters derived from small angle X-ray scattering (SAXS) measurements as developed for the characterization of two-phase systems. The SAXS method was also used for porosity determination in swollen samples. The differences in the porosity of dry samples were found to be an effect of the drying process, while in the swollen state the sample swells and deswells isotropically.

Temperature-dependent small-angle x-ray scattering from poly(vinylidene fluoride)

1980 ◽  
Vol 51 (10) ◽  
pp. 5508 ◽  
Author(s):  
J. M. Schultz ◽  
J. S. Lin ◽  
R. W. Hendricks ◽  
R. R. Lagasse ◽  
R. G. Kepler
Keyword(s):  
Small Angle ◽  
Vinylidene Fluoride ◽  
Temperature Dependent ◽  
X Ray ◽  
X Ray Scattering ◽  
Poly Vinylidene Fluoride ◽  
Ray Scattering

scholarly journals Supramolecular Dimerization in a Polymer Melt from Small-Angle X-ray Scattering and Rheology: A Miscible Model System

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 880
Author(s):  
Mariapaola Staropoli ◽  
Margarita Kruteva ◽  
Jürgen Allgaier ◽  
Andreas Wischnewski ◽  
Wim Pyckhout-Hintzen
Keyword(s):  
Hydrogen Bonding ◽  
Small Angle ◽  
Full Range ◽  
Polymer Melt ◽  
Self Healing ◽  
Temperature Dependent ◽  
Base Pairs ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

We present a structural and dynamic study on the simplest supramolecular hetero-association, recently investigated by the authors to prepare architectural homogeneous structures in the melt state, based on the bio-inspired hydrogen-bonding of thymine/diaminotriazine (thy–DAT) base-pairs. In the combination with an amorphous low Tg poly(butylene oxide) (PBO), no micellar structures are formed, which is expected for nonpolar polymers because of noncompatibility with the highly polar supramolecular groups. Instead, a clear polymer-like transient architecture is retrieved. This makes the heterocomplementary thy–DAT association an ideal candidate for further exploitation of the hydrogen-bonding ability in the bulk for self-healing purposes, damage management in rubbers or even the development of easily processable branched polymers with built-in plasticizer. In the present work, we investigate the temperature range from Tg + 20 °C to Tg + 150 °C of an oligomeric PBO using small-angle X-ray scattering (SAXS) and linear rheology on the pure thy and pure DAT monofunctionals and on an equimolar mixture of thy/DAT oligomers. The linear rheology performed at low temperature is found to correspond to fully closed-state dimeric configurations. At intermediate temperatures, SAXS probes the equilibrium between open and closed states of the thy–DAT mixtures. The temperature-dependent association constant in the full range between open and closed H-bonds and an enhancement of the monomeric friction coefficient due to the groups is obtained. The thy–DAT association in the melt is more stable than the DAT–DAT, whereas the thy–thy association seems to involve additional long-lived interactions.

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