ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
As model compounds for determining the potential adaptability of novel leaving group to polyamide synthesis, 2-aryl-5-benzoylthio-1,3,4-oxadiazoles having various electron accepting and donating groups in the oxadiazole unit were successfully prepared from the benzoylation of the corresponding 2-aryl-1,3,4-oxadiazoline-5-thiones under kinetically controlled conditions ( 〈 -50°C). The aminolyses of all the benzoyl thioesters by aniline afforded quantitative yields of benzanilide at room temperature in a short reaction time. Polycondensations of new active dithioesters, 5,5′-isophthaloyldithiobis-2-aryl-1,3,4-oxadiazoles, with both aliphatic and aromatic diamines occured quite rapidly even at room temperature to form polyamides with reduced viscosities up to 0.41 dL/g. The reactivities of the dithioesters having electron accepting groups such as p-chloro and p-nitro groups, particularly p-nitro groups, toward diamines were much higher than that of the dithioester having no such groups, but the introduction of electron donating p-methyl group had an adverse effect. The effects of reaction conditions such as solvent, temperature, and monomer concentration on the reduced viscosity of polyamides were also investigated. It was found that monomer concentration had a remarkable influence on the molecular weight of the resulting polyamides.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1985.170231101
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