## Abstract Poly(oxyethylene)s with number‐average degrees of polymerization (DP~n~) ranging from ≈ 6 to ≈ 80, terminated at both ends with phosphonium ion end groups (diionic poly‐EO), have been prepared and characterized as described in the preceding paper. Viscosities of diionic poly‐EO were mea
Poly(oxyethylene)s terminated at both ends with phosphonium ion end groups, 1. Synthesis and characterization
✍ Scribed by Przemyslaw Kubisa; Tadeusz Biedroń
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 643 KB
- Volume
- 197
- Category
- Article
- ISSN
- 1022-1352
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✦ Synopsis
The series of poly(oxyethy1ene)s (poly-EO) with number-average degrees of polymerization ranging from i i : 6 to i i : 80, terminated at both ends with phosphonium ion groups, was prepared by conversion of hydroxyl end groups of a-hydro-w-hydroxypoly(oxyethy1ene)s into bromide end groups, followed by the reaction with triphenylphosphine. The functionality of the products (diionic poly-EO) was determined by elemental analysis, 'H and 3'P NMR as well as mass spectroscopy (MS). The observation of the signals corresponding to individual oligomers in 31P NMR spectra of short chain (DP, < 10) diionic poly-EO was explained by intramolecular aggregation of ionic end groups leading to cyclic structures. The measurements of spin lattice relaxation times and the chemical shifts of phosphorus at different conditions (temperature, solvent, concentration) confirmed, that the aggregation of ionic end groups is clearly manifested in the 31P NMR spectra of diionic poly-EO.
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