SYNTHESIS OF N-SUBSTITUTED DIISOPROPANOLAMINES, THEIR SEBACATE POLYESTERS AND POLYURETHANE ELASTOMERS

1958 ◽  
Vol 36 (10) ◽  
pp. 1405-1409 ◽  
Author(s):  
Jean L. Boivin
Keyword(s):  
Aqueous Solutions ◽  
Infrared Absorption ◽  
Propylene Oxide ◽  
Sebacic Acid ◽  
Ionization Constants ◽  
Polyurethane Elastomers ◽  
Molecular Weights ◽  
Slight Excess ◽  
Infrared Absorption Spectra ◽  
Strong Acids

Several N-substituted diisopropanolamines were prepared by reacting aqueous solutions of amines with excess propylene oxide at ordinary pressure but higher N-substituted diisopropanolamines had to be prepared in an autoclave at 200 °C. The ionization constants of these bases were measured and recorded as pKa values. Their infrared absorption spectra gave bands common to all diisopropanolamines mainly at 3.04, 7.14, 7.55, 7.85, 9.45, 10.6, and 11.95 microns. Their condensation with sebacic acid gave the corresponding polyesters, which were soluble in strong acids and had molecular weights of about 1500. The hydroxyl-terminated polyesters were cured with a slight excess of 2,4-tolylene diisocyanate at 100 °C for 2 days to yield elastomers of brittle temperatures in the region of −50 °C.

SYNTHESIS AND INFRARED SPECTRA OF GUANYLUREAS

1954 ◽  
Vol 32 (3) ◽  
pp. 242-248 ◽  
Author(s):  
Paul A. Boivin ◽  
W. Bridgeo ◽  
Jean L. Boivin
Keyword(s):  
Carbon Dioxide ◽  
Nitrous Oxide ◽  
Aqueous Solutions ◽  
Absorption Spectra ◽  
Infrared Spectra ◽  
Infrared Absorption ◽  
Tentative Assignment ◽  
Infrared Absorption Spectra ◽  
By Products

When 1-amidino-3-nitrourea is reacted in aqueous solutions of amines, nitrous oxide and carbon dioxide are eliminated and guanylureas are formed, together with disubstituted ureas as by-products. The infrared absorption spectra of some disubstituted ureas and nitrates of guanylureas are discussed with tentative assignment of bands to some groups.

Chain Extension Studies Relevant to the Completeness of End-Linking in Elastomeric Polyurethane Networks

1982 ◽  
Vol 55 (5) ◽  
pp. 1464-1468 ◽  
Author(s):  
J. E. Mark ◽  
P. H. Sung
Keyword(s):  
Propylene Oxide ◽  
Relevant Information ◽  
Polymer Chains ◽  
Chain Extension ◽  
Polyurethane Elastomers ◽  
Molecular Weights ◽  
Before And After ◽  
End Linking ◽  
Poly Propylene

Abstract Polyurethane elastomers may be prepared by end-linking hydroxyl-terminated (atactic) poly(propylene oxide) chains with an aromatic triisocyanate. As is invariably the case, networks thus formed are insoluble and very difficult to analyze with regard to the completeness of the end-linking reaction. Relevant information can, however, be obtained by studying the products of the analogous reaction, between a structurally similar diisocyanate and the same polymer chains, under identical conditions. Since both reactants now have functionalities less than three, the reaction gives chain extension rather than crosslinking (gelation), and it is now possible to measure molecular weights before and after the reaction. Such experiments were carried out using diphenylmethane-4,4′-diisocyanate with poly(propylene oxide) chains which had viscosity-average molecular weights ranging from 10−3Mv=1.15−4.50 g mol−1. Values of Mv were found to increase by factors of 20–30, which indicates high extents of reaction. These results are relevant with regard to the probable efficiency of polyurethane curing techniques, and also for the characterization of “model” networks used in the quantitative evaluation of the molecular theories of rubberlike elasticity.

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