ISSN:
0449-2951
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Polymerization of one of the carbon-nitrogen double bonds in carbodiimides has been effected with n-butyllithium catalyst in hydrocarbon solvents at 25°C. Monomers converted to polymer include diethylcarbodiimide, di-n-butylcarbodiimide, di-n-hexylcarbodiimide, diphenylcarbodiimide, diallylcarbodiimide, and methylisopropylcarbodiimide. Monomers which failed to polymerize were dicyclohexylcarbodiimide, diisopropylcarbodiimide, and methyl-tert-butylcarbodiimide. Thermal polymerization and depolymerization of diethylcarbodiimide was investigated and the polymers were characterized. Polymers with an inherent viscosity of 0.1-0.4 (formic acid solvent) were obtained in this work. The steric limitations on the nature of the substituents at the backbone nitrogen and the pendant nitrogen of the polymer chain were elucidated. The cis-trans isomerism possible at the pendant nitrogen is discussed. The failure of a solution of polydiethylcarbodiimide in aqueous acetic acid (presumably a polyelectrolyte) to behave on dilution as a polyelectrolyte is tentatively attributed to the stiff polymer backbone. Depolymerization of these polymers appears to be an unzipping.
Additional Material:
5 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1964.100020907
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