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Topological Characteristics of Chain Molecules with Branching and Molar‐Mass Distributions
Macromolecular Theory and Simulations, 2021AbstractA graph‐theoretical method is presented for characterizing the statistical and dynamic properties of randomly and fixed‐branched chains that exhibit molecular weight distribution. The Wiener index, which is a topological index reflecting tree‐shaped structures, of any branched chain estimated from its random‐flight model (molecular graph ...
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Homogalacturonans from lime pectins exhibit homogeneous charge density and molar mass distributions
Carbohydrate Polymers, 2005Two series of lime pectins with different degrees and patterns of methyl-esterification were successively fractionated by size exclusion followed by anion exchange chromatography. ‘Homogeneous’ populations with respect to molar mass and charge density were thereby obtained and their physico-chemical properties were investigated.
Hellin, Pilar +3 more
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Molar mass distribution of vinylidene fluoride-3-oxaperfluorohex-1-ene copolymers
Polymer Science U.S.S.R., 1984Abstract The effect of polymerization temperature and pressure on M distribution of vinylidene fluoride-3-oxaperfluorohex-1-ene copolymers was studied. It was shown that M distribution curves of samples synthesized at 60 and 95° and a pressure of 24 atm are bimodal.
L.V. Pavlova +5 more
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Molar mass distribution of polybutadiene synthesized with nickel‐based Ziegler‐Natta catalysts, I
Die Angewandte Makromolekulare Chemie, 1994AbstractCis‐1,4‐polybutadiene was produced by polymerization of 1,3‐butadiene using a catalyst system formed by a two‐step formation, Namely (1) BF3 . O(C2H5)2 and Al(C2H5)3, (2) Ni(OOC8H15)2 and Al(C2H5)3 named in‐situ‐catalyst.The molar mass distributions (MMD) of the polybutadienes are investigated by means of size exclusion chromatography (SEC ...
K. Schröder +3 more
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Online control of molar mass and particle‐size distributions in emulsion polymerization
AIChE Journal, 2006AbstractProduct quality control is a complex issue in polymerization than in conventional chemical processes. The key polymer properties are related to the polymer particle‐size distribution (PSD), and molecular‐weight distribution (MWD), which are in turn sensitive to the thermo‐kinetic and operating history of the process.
J. Zeaiter, J. A. Romagnoli, V. G. Gomes
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The effect of molar mass distribution on extrudate swell of linear polymers
Journal of Non-Newtonian Fluid Mechanics, 2008zbMATH Open Web Interface contents unavailable due to conflicting licenses.
den Doelder, C. F. J., Koopmans, R. J.
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„Double Reptation Spectrum“ an Alternative Molar Mass Distribution - Material Function Conversion
1998The material functions MF of entangled polymer melts depend strongly on the molar mass distribution MMD of the polymer. The idea of double reptation [des Cloizeaux (1988); Tsenoglou (1987)] has brought considerable progress in modelling polydisperse polymers.
C. J. Brabec, A. Schausberger
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Inherent molar mass distribution of clones and properties of crumb natural rubber
2000Depending on the type of harvesting and processing adopted, the inherent molar mass distribution of natural rubber will govern the initial Wallace plasticity and the Mooney viscosity of the processed raw natural rubber. Two examples are described : constant viscosity processing from latex (5 CV 60 grade) and conventional processing from cup lumps (TSR ...
Bonfils, Frédéric +4 more
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Viscosity and compliance from molar mass distributions using double reptation models
Rheologica Acta, 2006Various empirical correlations between linear viscoelastic properties and molar mass distribution of linear polymers have been proposed. Many of these summarize the distribution in terms of the first few moments. This is sufficient when studying samples of limited variability.
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Molar mass distribution of polymers from sedimentation velocity in an analytical ultracentrifuge
2007An alternate procedure, the run time integral method, is suggested for precise determinations of molar mass distributions of polymers. The method is based on the fact that modern analytical ultracentrifuges directly measure the variable angular velocity ω as a function of time.
M. D. Lechner, W. Mächtle
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