ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Primary polyether polyamine oligomers containing preformed urea or amide moieties in their backbones were converted to the corresponding N-isopropyl polyether polyamine oligomers (secondary amines) by reaction with acetone and hydrogen in the presence of a catalyst. The best results were from reactions carried out at about 150°C using a supported platinium or palladium catalyst in a fixed bed. Reactants and products were monitored by quantitative carbon-13 NMR, size exclusion chromatography, and amine titration. Perchloric acid titration was used to quantify the number of urea moleties per molecule. Amide backbone materials gave very little backbone degradation. However, some backbone degradation was observed with urea backbone materials, leading to products with lower molecular weights. These polyether polyamine oligomers, containing urea or amide moieties in their backbones, are useful in urethane/urea polymer systems. The lower reactivity of these secondary amines (toward polyisocyanates) results in their utility in a broader range of polyurethane fabrication technologies. © 1992 John Wiley & Sons, Inc.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1992.070460906
