Light scattering from polyethylene solutions

Abstract

SynopsisThe technique of measurement of light scattering from dilute polyethylene (PE) solutions is reviewed. Conditions are discussed under which various PE samples can be characterized. The choice of the solvent affects the accuracy of molecular weight determination. It appears that measurement with thermodynamically poorer solvents yields results subjected to a smaller error. The interpretation of light scattering data is often disturbed by the presence of supermolecular structures in PE solutions. The effect of reprecipitation on the behavior of PE samples is described. The measurements were mostly performed on PE standards and on the Czechoslovak sample Liten Macro.

Use of continuous viscometer and light scattering detectors in characterization of polyolefins: Comparisons of data from individual and combined detectors

“…' Measurement obtained by using CV data and eq. (25). It can be seen here that the LALLS signal is the noisiest of these.…”

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“…( 13 ) , as well as eq. (25), to sum the individual intrinsic viscosities along the chromato- (25) [a1 =…”

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