Characterization of oligomers from 1,4‐butanediol and toluene diisocyanate
1993; Wiley; Volume: 47; Issue: 5 Linguagem: Inglês
10.1002/app.1993.070470507
ISSN1097-4628
AutoresMeta Lesar, Majda Žigon, T. Malavašič,
Tópico(s)Concrete Corrosion and Durability
ResumoAbstract Polyurethane oligomers from 1,4‐butanediol (BD) and toluene diisocyanate (TDI) with a various excess of BD were synthesized. Their molar masses were measured by gel permeation chromatography and the molar mass distribution correlated with the statistic theory. 1 H‐, 13 C‐, 1 H– 1 H‐COSY–, ATP–, and 15 N‐NMR spectra of reaction products were recorded, and from the ratio of proton integrals of characteristic terminal and inner urethane groups, the reactivity ratio of the para and ortho NCO groups in 2,4‐TDI was calculated to be approximately 1.8 at a lower excess of BD. 15 N‐NMR spectroscopy was found not to be selective enough to detect small amounts of side reactions. © 1993 John Wiley & Sons, Inc.
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