ISSN:
1572-8870
Keywords:
Polyphosphazene
;
polydialkylphosphazene
;
polyelectrolyte
;
phosphoranimine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Some dialkyl-or diaryl-phosphoranimines are so thermally stable that their thermal polymerization cannot be pursued: it follows that an alternative route to the synthesis of said polymers is to be found. The polymerization ofN-silyldiethylphosphoranimine with the aid of anionic initiators was studied. This reaction. compared with thermal polymerization. proceeded at a lower temperature and with a shorter completion time. Low molecular weights and often bimodal distributions were found.M m values obtained with Bu4NF and NaOPh were in the range 1000 10.000, with very narrow polydispersities. Since symmetrical disubstituted polyalkylphosphazenes with alkyl chains from C2 up to C8 are insoluble in organic solvents, their solution characterization in usual solvents was prevented. For this purpose, protonation reactions with organic and mineral acids were studied. The protonated polymers were found to be soluble in organic acids and in water, NMR spectra were registered. The molecular weights of the polymers were determined in 20% (v/v) acetic acid. The method, tested on samples of polydimethylphosphazene whose molecular weight was determined independently by membrane osmometry in chloroform solutions, was found to be reliable.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01062510
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