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Column fractionation of partially stereoregular poly(propylene oxide)
Date
1989-12
Author
Alyürük, Kemal
Hartani, Khaled
Metadata
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Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
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A column packed with glass beads has been used to fractionate partially stereoregular poly(propylene oxide) (PPO). PPO was first crystallized onto the glass beads from isooctane solution by stepwise lowering the column temperature. Each layer of PPO, which was deposited at different temperature ranges, was extracted by washing the beads with several columns full of isooctane. Thus several fractions differing in both stereoregularity and molecular weight were obtained by progressively increasing the extraction temperature and the solvent residence time in the column. It is concluded that in the procedure described above PPO can be fractionated on the basis of structural and steric regularity. The observed steady increase in the molecular weight of fractions with extraction temperature was interpreted as being due to the fact that the stereoregularity of chains increases with their molecular weight.
Subject Keywords
Organic chemistry
,
Polymers and plastics
URI
https://hdl.handle.net/11511/51749
Journal
Polymer
DOI
https://doi.org/10.1016/0032-3861(89)90270-x
Collections
Department of Chemistry, Article
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K. Alyürük and K. Hartani, “Column fractionation of partially stereoregular poly(propylene oxide),”
Polymer
, pp. 2328–2331, 1989, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51749.