Premium
Polymer fractionation by repeated extraction
Author(s) -
Klein J.,
Friedel H.
Publication year - 1970
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1970.070140802
Subject(s) - fractionation , extraction (chemistry) , homogeneous , solvent , polymer , phase (matter) , chromatography , materials science , fraction (chemistry) , solvent extraction , basis (linear algebra) , thermodynamics , chemistry , mathematics , physics , organic chemistry , composite material , geometry
All current fractionation techniques—based on sol–gel equilibria—are characterized by a variation of the solvent power after each fractionation step in a discontinuous as well as in a continuous way. Overlapping of consecutive fractions is the consequence of this procedure. It can be shown that this overlapping can be diminished essentially by a multistage technique based on complete extraction at a given solvent power which then will be changed in discontinuous steps. As a further consequence, it is possible to obtain very homogeneous fractions of M̄ w / M̄ n < 1.03. A theoretical analysis of this technique on the basis of phase equilibrium data will be given, the results of which can be confirmed experimentally.