✦ LIBER ✦

Estimation of polymer polydispersity by diffusion measurements at low concentration

✍ Scribed by M. Kubin; B. Porsch

Publisher: Elsevier Science
Year: 1970
Tongue: English
Weight: 403 KB
Volume: 6
Category: Article
ISSN: 0014-3057
DOI: 10.1016/0014-3057(70)90189-8

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✦ Synopsis

A method is described for calculating, from measurement of free diffusion by means of the wave front shearing interferometer, three different average diffusion coefficients which can characterize the polydispersity of a sample. The method was tested by measurements on a monodisperse sample, viz. biphenyl. The criteria of polydispersity were determined for two non-fractionated polymers, polyisobutylene and polystyrene. A comparison of calculated and measured number and weight average mol. wts. illustrates the scope of the method.

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