H. Kricheldorf, N. Lomadze, Claudia Polefka
Feb 24, 2006
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0
Influential Citations
23
Citations
Journal
Macromolecules
Abstract
Monodisperse oligo(ethylene glycol)s were polycondensed with trimesoyl chloride using triethylamine as HCl acceptor. Despite nearly quantitative conversions and relatively high concentrations (0.4 mol/L), no gelation occurred with tri- and tetra(ethylene glycol), regardless of the feed ratio. With a feed ratio around 1.5/1.0 multicyclic poly(ether esters)s free of end groups were isolated and characterized by 1H NMR and MALDI-TOF mass spectrometry. At concentrations of 0.2 or 0.4 mol/L di-, penta-, and hexa(ethylene glycol)s yielded gels. At concentrations ≥ 0.2 mol/L exclusively gels were obtained from various α,ω-dihydroxyalkanes. However, soluble multicycles were obtained from 1,8-dihydroxy-3,6-dithiaoctane and from 1,4-bis(2-hydroxyethoxy)-2-butyne. The influence of conformational differences on the cyclization tendency is discussed. The multicycles derived from tri- and tetraethylene glycol showed cryptand properties and dissolved Li-, Na-, K-, and Cs-benzoate in tetrahydrofuran.