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Molar mass distribution of diallyl 3,6-endomethylene-1,2,3,4-tetrahydrophthalate prepolymer
Polymer Science U.S.S.R., 1989Abstract Gel permeation chromatography was used to study the variation in molar mass distribution during benzoyl peroxide initiated polymerization of diallyl 3,6-endomethylene-1,2,3,4-tetrahydrophthalate in benzene solution. Whilst a linear polymer is formed initially, branched chains begin to predominate at higher conversions.
V.I. Kolegov +6 more
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Macromolecular Chemistry and Physics, 2000
The application of a poly(dimethylsiloxane) (PDMS) calibration curve for size exclusion chromatography (SEC) to poly(ethylmethylsiloxane) (PEMS) leads to molar masses, which are 15–40% higher than expected compared to measurements of the absolute molar mass values.
H. Götz +6 more
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The application of a poly(dimethylsiloxane) (PDMS) calibration curve for size exclusion chromatography (SEC) to poly(ethylmethylsiloxane) (PEMS) leads to molar masses, which are 15–40% higher than expected compared to measurements of the absolute molar mass values.
H. Götz +6 more
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Determination of molar mass distribution of alkyl polyethylene glycol ethers
Journal of the American Oil Chemists' Society, 1981AbstractA process based on gas chromatographic separation and on the computerized evaluation of the results has been developed for the determination of the distribution and distribution coefficients of alkyl polyglycol ethers, formed in the competitive, consecutive reaction of fatty alcohol and ethylene oxide.
L. Farkas +5 more
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Molar Masses and Molar Mass Distributions
1984In synthesizing polymers in vivo and in vitro, molecular homogenous (“monodisperse”) polymers (i.e., those in which every macromolecule has the same molar mass or “molecular weight”) occur only under quite specific conditions. The overwhelming majority of polymer syntheses proceed more or less randomly, and the resulting macromolecular substances have ...
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Influence of Molar Mass Distribution on Thermodynamics of Polymer Systems
1989For the description and prediction of thermodynamic data, e.g. volumetric and compositional derivatives of thermodynamic functions of state, many theoretical models are available. The Simha-Somcynsky theory can be considered to be very succesful if one is interested in the quantitative description of thermodynamic properties.
Nies, E.L.F., Stroeks, A.A.M.
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Influence of Molar Mass Distribution on the Compatibility of Polymers
Journal of Macromolecular Science, Part A, 1996Abstract Phase equilibria were calculated by means of a new method (direct minimization of the Gibbs energy of mixing) for polymer blends consisting of monodisperse polymer A and polydisperse polymer B. The results obtained for a Schulz-Flory distribution of B (molecular nonuniformity U = (M w/M n) −1 = 1 and 100 components of model B) agree ...
Sabine Enders +3 more
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Determination of Molar Mass and Molar Mass Distributions
1984Molar mass determination methods can be classed as absolute, equivalent, or relative. Absolute methods allow the molar mass to be directly calculated from the measured quantities without the need for assumptions concerning the physical and/or chemical structure of the polymers.
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Pearson-type I Distribution Function for Polydisperse Polymer Systems. Molar Mass Distribution,
Journal of Chemical Information and Computer Sciences, 2003This paper presents an attractive feature of the distribution function, which uses a relatively simple expression for approximating probability density. The Pearson-type I distribution function is used to represent the molar mass distribution (MMD) function for polymers for which the number average (M(n)), mass average (M(w)), z-average (M(z)), and (z ...
Bogdanić, Grozdana, Jakab, Lajos
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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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