ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A new class of polyureas are reported which contain a crown ether analog in the backbone. Synthesis involves condensation of 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane with either 2,4-toluene diisocyanate or hexamethylene diisocyanate in dichloromethane. The former gives tough, flexible polymers and the latter tacky, hygroscopic products. The infrared (IR) and proton nuclear magnetic resonance (NMR) spectra of these materials are given along with those of the polyurea from piperazine and hexamethylene diisocyanate. The carbon NMR chemical shifts and spin-lattice relaxation times are also reported. Comparison is made with monomer, other crown ethers, polyoxyethylene, and a model compound prepared from the diaza monomer and phenylisocyanate. The T1 values indicate a greater degree of backbone and macrocycle flexibility for the hexamethylene-containing polyurea than for the toluene analog.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1980.170181001
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