Zur fraktionierung von polymeren durch direktextraktion

✍ Scribed by Holtrup, Wolfgang

• Publisher: Wiley (John Wiley & Sons)
• Year: 1977
• Weight: 853 KB
• Volume: 178
• Category: Article
• ISSN: 0025-116X
• DOI: 10.1002/macp.1977.021780820

✦ Synopsis

Abstract

A method of solution fractionation by direct extraction is described for the purposes of determining molecular weight distributions and preparing almost monodisperse fractions. Unexpectedly, rapid phase equilibration is obtained by vigorous vibrational agitation of powdered polymers in corresponding solvent systems. In the case of high density polyethylene, phase equilibration proceeds within 5 min and is independent of particle size up to a diameter of 1 mm. Molecular weight distributions determined by the direct extraction technique deviate only slightly from those obtained by conventional gel permeation chromatography. Besides polyethylene also other well‐known polymers were fractionated by this method. It is especially well applicable to partially crystalline polymers, but less applicable to amorphous polymers.